This is a circadian rhythm type issue, chiefly the recovery routines should be set when not digesting foods.Morning routine changes a bit. Extra few hours of rest. Little things but I think they do help. Mostly psychological I guess. MaybeZest can put up a scientific explanation.
Tbh I've always noticed clubs struggling in early kickoffs after a European fixture. But a little less in an evening fixture.
Eating regularly let's the body, liver chiefly, prepare to release gastric juices and enzymes at the right time.
Once eating n digesting the autonomic nervous system will direct oxygen supply to the digestive system, hence best no significant protein 3-4hours before bed,to allow the sleeps recovery cycles to work optimally.
Then, if we apply this to a 12:30 kick off it muddies all kinds of biological processes...
If heavy exercise with intense cardio, whilst still digesting foods of complex nature (protein needs more oxygen), you have the perfect storm for impaired lactic acid buffering, for example.
Best I can convey in minutes, as working!