After inauguration of two more DD's 22117/8 and 22119/20, decided to check which all routes can accommodate DD, listed some.
1) Hubli - Bangalore DD
2) Madgaon - Mumbai DD
3) Solapur - Mumbai DD
4)...
more... Pune - Hyderabad DD
5) Madgaon/Mysore - Mangalore DD
Add few more on required lines