Specifically, the am peak.

I notice that it is 0630-0930 for peak single prices on the tube, but
the peak cap runs from 0400...(? - start of service).

Why can't they charge off-peak cap on travel prior to 0630, if no
further travel is done until after 0930 (and before or after the pm
peak)?

All the recording is computerised, so it should be simple to get the
programming right....so what's the reason?