43/44/45 do already interwork on the 'temp' frequency but can't do so if at normal frequency as too tight. Something else would need to interwork with 44/45 if eventually moved.

306/308 at the moment, would be better suited to a 10 minute frequency (20 each) to resolve driver shortage issues saving a PVR of 3-4, 306 if pulled out of Battle Hill could help reduce PVR by 4 if interworking (PVR would be 14x)