Maybe as you get closer to the Himalayas the transition altitude gets up a little and could quite well be over 25,000'. There more than likely are several different TAs and TLs.
I just had a quick look at the Indian AIP and infact there is a list of the different transition altitudes and they range from 4,000' to 23,000'
Have a look here, fourth page,
http://www.aai.aero/public_notices/E..._procedure.pdf
Regards,
BH.