This 12842 train should overtake Konark express between TDD and VSKP. By this, 12842 can reach VSKP before 9 pm, thus can further reach BBS by 3 am, and HWH by 11 am. The only reason, it gets so slacked timetable between BZA-VSKP because it has to trail the Konark express.
For 12841, I don't feel like any speeding up can be done, except some 10-15 minutes speeding between BZA-MAS.