Is there an indication of trust status? I.e. "auto imported" vs. Manually verified, and more importantly what happens when fingerprints change?

Yes, there's a Privacy Status in p≡p, there being four different states: no color (mostly today: insufficient crypto, weak crypto, unknown), yellow/orange for accepted, transparent and well implemented crypto, green for crypto avoiding the MITM (Man-In-The-Middle) possibility (after the involved peers checked their Trustwords and accepted them to be trustworthy) and red if the p≡p engine detects an attack.

Cf. the documentation for screenshots how this looks (nowadays): https://prettyeasyprivacy.com/docs

Messages from or to a contact can also show red, I forgot to mention, if the user decides that the key pair used by that contact is not trustworthy. That can make sense if you see from the contents of a message (and subsequently perhaps by a phone call, adding evidence to that) that someone's in between or the key pair in place is not really belonging to the contact, but made up.