As per a post above, my mortgage company wanted to increase my payments by 1% when we moved (and therefore let) due to service reasons. All it took was a letter and they waived this. I got the impression that both the 1% hike and military waiver were SOP.
That's pretty much correct...most mortgage companies apply a 1 - 1.5 % surcharge on "permission to let" and then immediately waiver it for serving military personnel.
You may be interested to know that there are in the region of the thirty thousand active complaints with the FS Ombudsman over this surcharge (I have one of them), so they may find it gets stuck right back up them in the way loan insurance has.
I ******** hate banks. And that pre dates the credit crunch by about thirty years.