Don't assume that one person can enter the dungeon more than once each lockout period. Everything else would make the lockout period itself obsolete.

This is an MMO and content is limited to certain sizes of groups, as in every other MMO, so you have to play favourite every now and then. It's your responsibility though to keep it fair and give people who have to sit out the priority on the next run, so nobody sits out twice in a row.

Either or, you'd be best to assume that you can't enter a dungeon more than once each lockout, so plan ahead based on that assumption.

The only thing I really hope is, that the lockout period is not gonna be something like 3-4 days...rather 2days max, cause everything else would suck right now. There is not much to do and then being limited to something "new" only 1h every 4 days and then possibly having to make people sit out on that and wait another 4 days would really suck.