Ball Breaker, I'm leaning towards agreeing with DalDude on this... my unit gave out approximately 600 sets of manday orders a year, and in order for several exemptions to apply, the order had to state "in support of contingency operations" on the back. If it was left off your order, you had to get an ammendment for it. However, from about 2008 and on, this sort of "manday" was almost non-existent from AETC at least, they were very limited in number. There was a limit of how many mandays you could work in one year, 132 or something? Which could go up to 178ish if it was contingency ops. And then they increased it to 1000 MD in any 4 year period (I think).
In any case, orders that satisfied the title 10 "in support of contingency ops" specifically had to state it on the back, and this was an item that was checked and double-checked and argued up the chain and back down, result being these days/orders grew increasingly fewer through last year. Having orders of this sort gave a tax benefit as well as allowing more days / year, I believe.

Of course we all hope that no one is lawyering up to argue about every order over a > 5 year period, and that all our bros make it back to the property safely... but the fact remains, if you DO go over 5 years on mil leave, there are complex rules in place that didn't just show up for no reason, and it's possible to not be in compliance---it behooves you to check it out carefully, not assume, and be cautious with your continued employment risk if you're in this category.