That is a great observation and question - yes, in almost all of the cases I know of when top AGers are reaching the 20+ hour mark in training they have the week fully off work (holidays, maybe retired, etc.) . The effort needed for 20+ hour weeks also needs significant attention to rest, sleep, nutrition, hydration, sports massage, etc.

Remember most of these athletes also have large bases over many years so they have learned to adapt to a higher amount of duration and intensity so this is a progression from their normal 12-15 hours per week. A big week or two like this is almost certainly followed with complete rest days and easy active recovery days. The idea is to over stimulate the body and mind without breaking anything then allow the training to be absorbed.