How often should EBF baby feed during the day?

I returned to work so my 3 month old is in daycare 2-3 days a week. The same time I went back he started sleeping 8-10 hours overnight. I nurse at home and send bottles to daycare. My problem is he isn’t eating much at daycare. He nursed at 4:15 am, only ate ~12 oz from 5 am-6:45 pm. Nursed twice after that and fell asleep for the night at 9:15 and slept until 7am. He is always offered a bottle before daycare at 7am but has refused it both times. There’s no way he’s getting a minimum of 24 oz. Idk what to do because he just isn’t interested in eating. He’s such a happy baby and was gaining weight, but I’m afraid he’s going to start losing weight. Prior to going back to work he was nursing 9-12 times a day. He’s found his thumb so idk if he’s choosing his thumb over nursing? He doesn’t take a pacifier.

If he continues to sleep through the night should he still be nursing 8-12 times during the day? I feed him on demand on my days off, but he’d basically be nursing hourly to hit 12x (which he so far is not doing).

Help a concerned mom out 😩