I was on dread yesterday and they said that tor is needing more guard nodes because it's under a denial of service attack so if you can either run one or there are several places where you can apparently donate money and someone will run one for you then you should do that.
I saw they removed some 600 guards that were running old end of life versions of tor. Was your contact information correct and have you checked that email?
I've gotten contacted before so I assume that's all gravy. Anyway, my relay is healthy and up to date as far as I can tell.
I do assume that me not being a guard anymore is just some automatic defensive mechanism that'll sort itself out in the long run; not too worried about it, just curious.
There's been a major DDoS against guard nodes lately as well, causing many of them to lose connecting clients so it may have been unaccessible for long enough that it kicked back to relay but I'd ask on the relay-operators mailing list/forum. They've been posting a lot of firewall rules and scripts to fend off attacks.