Date changing concern

Hey guys,

I just joined this cool forum now that i am a proud owner of an omega seamaster chronograph. I bought it mint condition online and ive had it for a days and i'm in love. Just a quick question, I noticed that the date changes somewhere between 4-5 am, it this normal? I was expecting the watch to change the date exactly at midnight. I realized this today to make sure i had my AM/PM set correctly and found it weird that the watch changes the date around those hours?

Any help would be greatly appreciated, thanks !