PLMN Scan Rate when off network

Hi Baseband, I'm trying to figure out if there's any standard set for how often a handset should scan for signal when out of coverage. I haven't been able to find much, just the following in 3GPP TS 22.011: 3.2.2.2 At switch-on or recovery from lack of coverage If registration cannot be achieved on any PLMN, the UE shall indicate "no service" to the user, wait until a new PLMN is detected, or new location areas of an allowed PLMN are found which are not in the forbidden LA list(s), and then repeat the procedure. When registration cannot be achieved, different (discontinuous) PLMN search schemes may be used in order to minimize the access time while maintaining battery life, e.g. by prioritising the search in favour of BCCH carriers which have a high probability of belonging to an available and allowable PLMN. Sounds like it's up to each manufacturer to just pick a delay? Any other thoughts/intuitions which might help us bound this number? Thanks!