I get an Army Pension, its index linked, and whatever your due to get monthly, on the day it starts, your 60th Birthday, you also get a lump sum, three times whatever you would get in a year, a one off payment, (comes in handy)
If you want to get in touch, they'll tell you what you want to know, 0800 0853600
Doesn't actually answer your question, but I hope it helps a bit.