I get up at 6am for work. DH (SAHP) gets up at 8am ish with DS. He reckons that on my days off if I get up with DS at 8 and he stays in bed until 10 it would be fair because we'd both be getting 2 hours lie in.
I think his logic is mean, surely he gets 2 hours extra in bed every day I'm in work early so 6 - 8 hours a week? So on at least one of my days off I should probably stay in bed until lunchtime to catch up? 
AIBU to think DH's logic is flawed and that he needs to share out lie in time more fairly?
WIBU to just stay in bed in protest until he agrees that we both get one morning each until 9 / 9.30 instead?
Should I LTB 