What parts are you concerned about? There's a support article about which parameters are retained. Ext/pass and everything it needs to get online. There are a few call center related settings that aren't preserved across reboots without the 46xx. I'd imagine trustcerts has to be in there. Haven't checked if a PKCS12 is, but I reckon it'd have to be. Either the phone gets it delivered by settings file, or it gets it via SCEP. You can't just SCEP all day long/every time you reboot - the authority might enforce only renewing with <20% validity time left - so the phone would be useless if it didn't remember it's cert.