One children's chewable Benadryl helped my daily hives. I had an outdoor cat so didn't know I was allegic to him until he got sick and spent too much time on my lap in the evenings; I'd break out in really bad hives, welts on my neck that itched like heck

It wasn't until after he died that I realized what they were from (they stopped :-) There's a good chance that an owner will grow accustomed to one's own pets over time and my two cats now are much more lap-friendly than my previous cat but I don't get hives from them.

I would look at everything that may have changed in your life since you've gotten the hives regularly, especially everything you do at that time of day. Could be a med you take then too, that side effect could wear off and then rear up again the next day when you take the next pill.