The update I received yesterday (4/12/19) on my unlocked S10+ appears to have fixed this issue!
I concur! The March update fixes the Caller ID and Spm Protection from turning off after rebooting the phone!
Same here. I got the ASD3 update early on 4/13 and Caller ID and spm protection hasn't turned off since.
Side note: Why is the word sp@m not allowed in the forum? It's not like an actual spammer is going to put that word in their post. lol