Can we try making a list of extended trains? I know its going to be endless as many trains were extended many times and might be, from both the ends. Atleast we can try this. Senior members can help over here. I'm putting down those which I know (number 1 to 11, I know more but forgot listing them then):

1. TATA SPJ to MFP, GKP and then (detention) to CPR and now to THE and viceversa
2....
more...

SDAH NDLS Duronto to BKN and vice versa
3. MMCT JP Duronto to HSR and vice versa
4. BDTS JP G Rath to NZM
5. TATA/BKSC MAS to ALLP and BKSC MAS to DHN
6. ST HTE to MDP
7. GHY Raj to DBRG
8. BSP Raj to HWH and again detention to BSP
9. MMCT ADI Duronto to HAPA
10. TATA PNBE South Bihar to DNR and then to ROU/R/DURG. Now detention to RJPB
11. PNBE Raj to RJPB
12.Bilaspur - Bhopal Chattisgarh Express to NZM and after that ASR
13. Sambalpur - NZM Hirakund Express to VSKP and ASR
14. Bilaspur - VSKP Link Express to Korba
15. Bilaspur - Ers Cochin Express to Korba and TVC
16. Bilaspur - YPR Wainganga Express to Korba
17. Nagpur - Nzm Gondwana Express to BSP/RIG 5 days and BSL 2 days
18. Sc - Nagpur to Raipur
19. Ngp - Ltt Jnaneswari Express to HWH
20. Vidarbha Express to Gondia from Nagpur
21. NGP SC to R
22. ADI SVDK Sarvodaya to GIMB
23. ADI-BJU 09483 to ASN once a week
24. RNC-BGP 08603 to GODA
25. ST BSB Tapti Ganga to CPR
26. ST PNBE to BGP
27. Ganga Jamuna (DLI BSB) to BNW and DNR then detension to DLI and extended to MLDT
28. Shramjeevi to RGD
29. BL SEE to MFP
30. BL PNBE to BDTS
31. MS ASN Ratna to JSME and to MS
32. RNC JYG to ROU
33. BDTS GIMB Kutch to BHUJ
34. Swaraj to SVDK
35. Jammu Mail to SVDK
36. BRC Mahamana to KDCY
37. REWA Mahamana to KDCY
38. GJSK to KDCY
39. HTE DLI Exp to PTKC, JAT and to ROU, SBP
40. ALD LKO to CPU and then to SGRL/SKTN and then to BE, then TPU. Renamed as Triveni Exp
41. DBG-NZM Garib Rarh to JYG
42. JAT-BJU Amarnath to BGP
43. RJPB-NZM Garib Rath to BGP
44. HWH-BHP KaviGuru to BGP, now JMP
45. BGP-NDLS weekly to GODA (converted to HS)
46. GKP-NDLS Gorakhdham Exp to Rohtak, then Bhiwani and then Hisar
47. BJU NDLS Vaishali to SHC
48. DBG NDLS Swatantrata Senani to JYG
49. ASN-ASR exp to SDAH now KOAA now known as Akal Takht Express
50. Parasnath Exp to ASN from DHN and to BVC from ADI
51. HWH TATA Ispat Exp ROU, JSG, SBP, TIG
52. Sdah-njp padatik first upto NCB then NOQ
53. Bbs-Nzm hirakud exp 1st extended to ASR then Vskp
54. Shm-bqa Aranyak exp 1st to Adra then to Santaldih and now BJE
55. Mas-Bsb Ganga-kaveri unfortunately upto Chapra
56. Ddn-ndls nandadevi to Kota
57. Devagiri (CSMT-AWB) to NED, MUE, NZB, then to SC
58. LDH-BSB Kisan Exp to FZR & DHN (now Ganga Satluj Exp)
59. NGP Gaya Deekshabhumi to DHN, other side to PUNE, KOP
60. PNBE DHN Patliputra Exp to HTE
61. BBS HTE G Rath to BKSC, DHN
62. HTE - PNBE Super got extended to RJPB. Then again it was short terminated at PNBE and RSA with Kosi Express started. Then, it was extended to Saharsa. Then to Murliganj and finally to Purnia Court.
63. DHN GAYA to Dehri On Sone
64. Howrah Tata Passenger to Chakradharpur
65. Howrah Bokaro Shatabdi to Ranchi
66. Howrah Asansol Fast Passenger to Dhanbad & converted to Black Diamond Express
67. Kolkata Anandpur Sahib Express to Nangaldam
68. Shalimar Bankura Rajyarani Express to Adra
69. Sealdah Pathankot Express to Jammu Tawi
70. Sealdah Delhi WBSK to Amritsar once a week
71. Sealdah Ajmer Ananya Express to Udaipur and terminal change to Kolkata Chitpur
72. Howrah Chopan/Singrauli Shaktipunj Express to Jabalpur
73. Kolkata Bhopal Express to Ratlam, Ajmer, Ahmedabad
74. Howrah Samastipur Express to Muzaffarpur & Raxaul Mithila Express
75. Howrah Sainthia Mayurakshi Express to Rampurhat
76. Sealdah Chhapra Gangasagar Express to Darbhanga & Jaynagar
77. Sealdah Katihar Hate Bazarey Express to Barauni & back to Saharsa
78. Sealdah Delhi Lal Quila Express to Jaipur & back to Delhi
79. Howrah Delhi Toofan Express to Sri Ganganagar i.e. Toofan merged with Udyan Abha Express
80. Howrah Kiul Passenger via SBG Loop to Barauni, Muzaffarpur, next to Darbhanga & lastly Jaynagar
81. Sealdah Mokama Fast Passenger to Barauni, Samastipur, Muzaffarpur & lastly to Sitamarhi with conversion into Express
82. Howrah Danapur Fast Passenger to Rajgir
83. "Howrah Varanasi Express & passenger to Jaunpur" extended to Lucknow & finally to Amritsar as Express train
84. Howrah Bankura Shiromoni MEMU to Adra as conventional train
85. Howrah Varanasi Vibhuti Express to Prayagraj Rambag
86. Mumbai Nagpur Samarsata Superdeluxe to Howrah
87. Kolkata Darbhanga Mithilanchal Express to Sitamarhi
88. Howrah Samastipur Express to Gorakhpur, Kathgodam as Bagh Express
89. Kolkata Chittaranjan Passenger to Jasidih
90. Howrah Rampurhat Ganadevta Exp to Azimganj
91. Howrah Rampurhat Intercity Exp to Pakur, Malda Town
92. Howrah New Jalpaiguri Kanchanjunga Express to Guwahati, Silchar, Agartala
93. Sealdah NJP Kanchankanya/Uttarbanga Exp via BAK Loop diverted via SBG Loop & extended to APDJ & NCB respectively
94. Kolkata Berhampore Court Dhano Dhanye Express to Lalgola
95. Kolkata Murshidabad Hazarduari Exp to Lalgola
96. Nabadwip dham New Farakka Express to Malda
97. Howrah Bhagalpur overnight Express to Jamalpur
98. New Bongaigaon Cochin Harbour T Express to Silchar & Trivandrum
99. Howrah Guwahati Kamrup Express to Dibrugarh
100. Puri Darbhanga Express to Jaynagar
101. Howrah Bhubaneswar Dhauli Express to Puri
102. Howrah Tiruchchirapalli tri weekly to CAPE once a week
103. Vasco Vijaywada Express to Howrah
104. Dhanbad Muzaffarpur Express to Hatia & Gorakhpur as Maurya Express
105. Jaipur Bilaspur as Jodhpur Puri
106. Jodhpur Jaipur Intercity, to SWM, KOTA. Now Jodhpur Indore Ranthambore
107. Kota GKP to MFP, now as Bandra - Barauni Avadh
108. Delhi Exp to Dehradun as Dehradun Exp
109. Mathura Patna to Kota.
110. Mathura - Prayagraj to Jaipur
111. Kota - Jabalpur to Jaipur then Ajmer as Dayodaya Exp
112. Kota Gwalior to Bhind, then Etawah
113. Kota Bina to Damoh then Katni, finally Jabalpur
114. Lichchavi (MFP ANVT) to SPJ then to SMI, skipping SPJ
115. JHS LKO Mail to CPR and now to BJU and other side to GWL
116. Mourdhwaj (SEE-JAT) to BJU
117. BSB LTT Pawan to MFP, DBG, JYG
118. Swatantrata Senani from DBG to JYG
119. Raptisagar Exp- GKP to BJU
120. Vindhyachal Exp from BINA to BPL (i.e merger of ET KTE and KTE BPL Exp)
121. Taj from GWL to JHS
122. Nagda Guna to Bina
123. MLDT JMP to KIUL
124. Tirupati Vskp Tirumala exp from BZA to CCT then VSKP now HX
125. Chennai Vskp weekly to BBS
126. Vskp SBC prashanti to BBS
127. SC Vskp Visakha exp from VSKP to CHE then to PSA now BBS
128. BBS Vskp intercity from PSA to CHE, VZM now Vskp
129. CCT SBC sheshadri from TPTY to SBC
130. BZA Vskp night passenger to RGDA , GNT
131. KOP HYB exp to MUGR
132. GNT SC palnadu to VKB
133. MTM SC to Bidar
134. Tirupati HYB Rayalaseema to NZB
135. Krishna exp SC to BZA then GNT, TPTY then SC to Adilabad.
136. Vskp BZA Janmabhoomi to TEL
137. SC GNT nagarjuna to Tenali then combined Vskp to SC janma bhoomi now to LPI
138. CSMT to SC Minar exp and SC BBS Konark Combined
139. Golconda BZA to SC to GNT.
140. SC BZA intercity to GNT
141. Venkatadri exp TPTY to CTO
142. KCG to SSPN to YPR
143. YPR Solapur Basava to Bijapur then MYS.
144. Solapur YPR SF to HAS
145. Chennai SBC Shatabdi to MYS . Now most trains of SBC extended to MYS.
146. SBC HWH weekly to GHY
147 Bhopal-Rajkot Express to Jabalpur from 1 end and Veraval then Somnath at 2nd end.
148. Bhopal-LTT Janta Express to Lucknow then Gorakhpur (now Kushinagar Express)
149. Bhopal-Chhindwara Passenger to Indore
150. Shatabdi Express from Jhansi to Bhopal, Habibganj
151. Bhopal-Bilaspur Chattisgarh Anchal Express to NZM then ASR
152. Bhopal-Lucknow Superfast to Pratapgarh
153. Habibganj-Bandra Special to Jabalpur
154. Uttar Banga to Bamanhat
155. GHY TVC Aronai to SCL
156. GHY TBM to SHTT
157. SHTT DBB Rajyarani to APDJ
158. Poorvottar S Kranti to SCL
159. NDLS JP Shatabdi to AII and then to DOZ. Detention upto AII
160. ERS JP Marusagar to AII
161. KYQ JP Kaviguru Exp to UDZ
162. JBP JP Dayodaya to AII
163. JAT DLI Pooja Exp to JP then AII
164. CDG JP Garibrath to AII
165. KGM DLI Ranikhet Exp to BGKT then JSM
166. BDTS JP Garibrath to DEE
167. DLI JP Intercity to JU then JSM /BME
168. Durg JP Exp to AII
169. SDAH JP Exp Convert in HWH JU/BKN SF
170. Kota JP Exp to HSR
171. BDTS JP Aravali Exp to SGNR
172. ADI DLI Yoga Exp to HW then YNRK
173. BE AII Ala Hazrat to GIMB, then BHUJ
174. HW AII Exp to UDZ & YNRK
175. UDZ JP Exp to GWL then KURJ
176. Kalinga and Utkal Express merged to form PURI HW Kalinga Utkal Express. Now extended upto YNRK
177. Avadh Assam to DBRG and to LGH on other side
178. BPL AII Exp to JP
179. JP BKN Leelen Exp to JSM
180. KOTA HMH SF to JLWC & SGNR
181. ADI AGC SF to GWL
182. GHY JU Exp to BME
183. HYB AII Exp to JP
184. Kolhapur Nagpur Maharashtra Exp to Gondia
185. Ratnagiri from BSB to GKP
186. SC DNR from BSB to PNBE then DNR
187. Lucknow Kota to Patna
188. Lucknow Indore to Patna
189. Sarnath Express BSB to CPR
190. Lucknow Shatabdi was initially Cnb - Delhi
191. Patna - Chennai Express to Bangalore City from Chennai Central and renamed as Sanghamitra Express
192. Bagmati Express from Bangalore City to Mysore.
193. Danapur Katihar capital Express (daily) extended 3 days to njp and 4 days to kyq.
194. Delhi Katihar mahananda Express link Portion extended to njp then complete train extended to APDJ
195. Jyg-KIR (janki express) extended to manihari.
196. Barauni- Amritsar jansewa Express extended to SHC
197. Dbg-asr (Saryu Yamuna and Shaheed) extended to JYG.
198. Hwh-mldt fast pass converted into exp and extended upto kir (daily)
199. AGTL-ANVT tripura sundari to FZR
200. Amrapali Express (SPJ CNB) to NDLS BJU, then to DLI KIR now ASR KIR
201. Hirakud was originally a sbp-nzm was then extended to bbs. Afterwarfs, extended to asr and vskp both ways.
202. Ahimsa upto bhuj, veraval, jodhpur
203. Durg Jaipur to Jodhpur and Bilaspur, now Puri Jodhpur
204. Sasaram G Rath to Gaya
205. ASR JP Exp to AII
206. JP CDG Exp to DLPC
207. BKN MAS Anuvrat AC Exp to MDU
208. BGKT TBM Humsafar to TPJ
209. NZM BPL Shan E Bhopal to HBJ
210. NDLS CNB Shatabdi to LJN
211. NZM MAS Rajdhani to TVC & Diverted Via KR Region
212. NZM AGC Gatiman Exp to JHS

Plz help expanding this list

Please Post Here All IRTTC 2021 NWR and Other Zone details... It will helpful for IRI Fans to find all details in a single blog... #NWRIRTTC #IRTTC2021

UPDATES :-

...
more...

(*) - Only proposed
(√) Approved Confirm By RO (without Official letter)
(√√) Approved with Official Letter
(®) Rejected

1) JP Duronto To HSR (IRTTC 2019/20) - ✓√
2) JP - PUNE To DD & Frequency Increase To 5 Days √
3) MAS - BME Weekly Express √
/blog/post/4959354
4) AII-YNRK Daily ICE √
5) HSR MAS weekly * via CUR JP SWM BPL NGP
/blog/post/4959354
6) BKN DEE Exp to JSM *
/blog/post/4959354
7) Marusagar and Ajmer puri Extension to SGNR ®
8) UDZ SGNR Exp new train √
9) Purushottam Extension to Jaipur *
/blog/post/4959354
10) AII AF SF extension to BME ®
/blog/post/4959354
11) JP BIDR Exp New Train √
/blog/post/4959354
12) SGNR TKBJ extension to Kanpur √
/blog/post/4959354
13) DLI HSR Via RE Pass Permanent Cancelled √
/blog/post/4959354
14) ADI SVDK via JOR HMH FZR *
/blog/post/4959354
15) SGNR SRC Biweekly Humsafar New on Toofan Route√
/blog/post/4959354
16) Any Jodhpur Delhi (Mandore/Salasar) train extension to Barmer *
/blog/post/4959354
17) JP SOG Pass speed up √
/blog/post/4959354
18) HSR CBE AC SF extension upto SVDK*
/blog/post/4959354
19) UDZ ASN Exp Via Kota New train*
20) SBI KGM New weekly Exp via AII JP√
/blog/post/4959354
21) JP INDB Triweekly New*
22) KKDE DLI Memu Extension to Rewari√
23) ROK DLI memu Extension to Rewari√
/blog/post/4959354
24) KLK DLI Pass Converted into Exp with Rewari Extension √
/blog/post/4959354
25) ASR BGKT Weekly Via HSR *
26) ASR BDTS Biweekly Via HSR CUR SIKR RGS FL*
/blog/post/4959354
27)CDG BDTS Biweekly to Daily *
/blog/post/4959354
28) Pooja Exp Extension to DOZ *
/blog/post/4959354
29) DEE BKN Via SGNR Short termination at LGH√
/blog/post/4959354
30) BKN HWH Triweekly Extension to LGH*
/blog/post/4959354
31)BNW MTJ and MTJ KOTA merged BNW KOTA*
/blog/post/4959354
32)SSA HW Intercity Exp Via HSR ROK TPZ√
/blog/post/4959354
33)CDG ADI Weekly Via RE RGS FL AII ABR *
/blog/post/4959354
34)BGKT KURJ Weekly New*
/blog/post/4959354
35) AII CDG Garibrath into Humsafar√
/blog/post/4959354
36) Champaran Satyagraha extension to JU*
/blog/post/4959354
37) AII RMM Humsafar Extension to FZR√
/blog/post/4959354
38) 19415/16 ADI SVDK Exp Diversion*
/blog/post/4959354
40)Marudhar Exp Extension to Varanasi City
41)Ashram and Mandore Extension to Meerut City
42)Bhramputra Mail Extension to Jodhpur
/blog/post/4959354
43) JP MTJ Intercity Exp Via AWR*
/blog/post/4959354
44)Sainik Exp Triweekly to Daily®
/blog/post/4959354
45) Jaipur Sadulpur New Intercity Via RGS SIKR JJN LHU
46) Jaipur Rewari New Train Via RGS NMK NNL
47) Jaipur Amritsar Via SIKR HMH SGNR new train
/blog/post/4959354


OTHER ZONE's PROPOSAL:

1) BDTS KLK Triweekly New √
/blog/post/4959354
2) SVDK KOTA Exp extension to Indore√
/blog/post/4959354
3) CDG DD Weekly via NDLS KOTA PUNE√
/blog/post/4959354
4) BPL SWD Exp New*
/blog/post/4959354
5) INDB MAS Exp
/blog/post/4959354
6) Navyug Exp Diversion DSJ skip NDLS*
/blog/post/4959354
7) UMB NZM Pass Converted into Exp with MTJ extension√
/blog/post/4959354
8) KLK SNSI Exp Extension to DD√
9) ASR Jaynagar Bi Weekly *
/blog/post/4959354
10) JAT INDB Extension to DADN√
/blog/post/4959354
11)UHP Durg Exp Extension to DRZ
/blog/post/4959354
12)TATA ASR Weekly New*
/blog/post/4959354
13) LKO UBL Biweekly New*
/blog/post/4959354
14) NZM UBL Triweekly New*
/blog/post/4959354
15) BE BSP Exp Via LKO RBL PRYJ KTE*
/blog/post/4959354
16) FZR BBS Biweekly via ROK DSJ JHS APR BSP*
/blog/post/4959354
17) 5 Trains Terminal shifted from DEE
/blog/post/4959354
18)Firozpur Cantt Delhi Exp merge with Patalkot Exp√√
/blog/post/4959354
19)Hubballi Danapur HS Via pune BSL JBP DDU*
/blog/post/4959354
20) CDG TPTY Weekly* UMB SRE NZM JHS NGP SC
21) CDG CAPE Weekly*
22) AADR NDLS ICE * via CDG UMB SRE MTC GZB
/blog/post/4959354
23) MDP Pune Weekly Exp*
/blog/post/4959354
24)SGRL ANVT New SF*
/blog/post/4959354
25)ASR DD Weekly √
26)BDTS YNRK Weekly √
/blog/post/4959354
27)SVDK JBP Regular√
/blog/post/4959354
28)ANVT MZS Weekly SF*
/blog/post/4959354
29) ASR Puri Weekly *
/blog/post/4959354
30)MAO UDN Exp Via RN - PNVL - BSR - BL*
/blog/post/4959354
31) LKO YNRK New Weekly*
/blog/post/4959354
32)Kamayani Exp Extension to Chhapra
33)Okha Varanasi Exp Extension to Chhapra
34)Sabarmati Exp Extension to Darbhanga
35)Sangam Exp Extension to SRE/UMB
36)NDLS ROK Memu Extension to Jind
/blog/post/4959354
37)BPQ/KZJ - NZM new via BTC - NIR - JBP*
38)22457/58 AADR - NED Express shift of days from Friday to Tuesday
/blog/post/4959354
39) Maharashtra Exp merge with ITR Rewa Exp
/blog/post/4959354
40) GTNR SVDK Bi Weekly Exp via MKG CNB NDLS
/blog/post/4959354