I would aim to get him into bed about 7.15/7.30. Did you do set naps and bedtime previously to this hiccup?
I would base suitable wake up on time he's asleep YK? So if he's asleep by 7.30, I'd expect him up at 6.30am so if you want a later wake up then you maybe need to set getting into bed at 7.30 and then push it toward 8 to hopefully get a 7am wake up. But did you mention not wanting a later bedtime?
The molars could be at play though so I'd only make small changes. I always found set times best at this age and only altered by 10/15 mins at most.