There is some effect at work here though, individual experiences may differ. If I eat one meal per day after that meal I will feel lazy and quite tired.

So if I finally ate at 6pm, hours later than 6pm I would feel like sleeping.

If I finally eat any later than 6pm I will start getting weak/shaky beyond 6pm.

This isn't a result of lack of acclimation. I've done fasting for 4+ month stretches multiple times in the past 6 years and have even experimented with 24+ hour fasts on a regular basis.