My best advice is to be a polite, squeaky wheel.
I've been told more than once by Frontier techs and supervisors that speed upgrade decisions are made by demand. If they get a lot of calls for them by an area they move up on the waiting list. Do you have neighbors you can encourage to call and request it? If you've got a hometown newspaper you could write them, and attend a city/township board meeting to let them know so the info can be inserted into the minutes and get coverage.
We The Desperate resort to some pretty odd tricks (I didn't have DSL until last year) to get someone -- ANYONE -- to deploy, but it pays off when it works. Good luck!