Nah, I wouldn’t worry. * Boys are in general later with toilet training than girls * and staying dry through the night typically takes longer for kids to master than having accident-free days because nighttime potty training is contingent mainly on physiological development.

My son still had regularly night time accidents till he was 10/11yrs old. We never put him in pull ups during the night after he started Kindergarten. We did reduce his liquid intake in the evening and would take him to the toilet before we went to bed ourselves. We had a mattress with a plastic cover and when he was wet during the night he would wake me up and we would together take the bedding off, put it in the washing machine and put new bedding on. Without making any negative comments

I know this is probably obvious, but are you getting him to go to the toilet before he goes to bed? Maybe he is too tired with the later bed time and is sleeping too soundly and doesn’t realise he is doing it?