A few corrections to "what you have been told", all from 18 Pa.C.S. 6109: Licenses...
That said, it is well known that some Sheriff's allow themselves great liberty with the statutes, however this is the law and your Sheriff will be in violation of it if he operates outside these parameters.
Edited to add: The process for renewal is identical in every way to the process for the initial application. It certainly does not "take any longer", although they could easily drag it out on purpose. When my wife and I got our PA LTCFs in York County the entire process, from investigation to photo-taking, to the printing of the license, took 10 minutes.
10 minutes. I'll pause here for a bit for the shock to wear off.
I put money in the parking meter to allow for 30 minutes, and there was 15 minutes left when we got back. That included the round trip walk.
I can see possibly taking a couple days and having you come back to pick it up in the event they are really, really busy, but any Sheriff making you wait any longer than that is jerking you around just because he can. You either have a record or you don't, and the operative word in the NICS/PICS system is "instant".
If you sense some irritation in my post it's because the behaviors exhibited by some of our "public servants" chaps my ass a bit from time-to-time.