Eye of terror during day

I'm not sure how it happened, but about a couple weeks ago i think, maybe a month ago, i was playing a world where everything was on default settings for endless mode i believe, and i was playing alone. Playing on pc. I first summoned it at day 30, the same day that deerclops spawned but before her spawning sound started playing, so i let them battle it out and then i left the eye of terror alone for the rest of the night after i grabbed the loot of deerclops thinking i wouldn't be able to finish the fight that night. I wasn't around to see eye of terror despawn that night. then maybe around 10 days later i decided to fight some clockworks which i had to walk past the terrarium to do, and along the way i found 3 sets of beefalo loot lying on the floor so i looked around and saw the eye of terror just wandering around early that day. I used rollback a couple times i think between the days i didn't fight eye of terror so maybe that had something to do with it? I rollbacked on the day i found eye of terror roaming around and walked back to the location and eye of terror was still there, roaming the world during the day. I don't think this has anything to do with this bug happening but i was playing as wendy.