You can re-time every fixture in a group in one go. Only the tournament Owner and an Administrator can do it; everyone else sees the read-only public page.

One tick box decides whether this works the way you expect. Same start time per round is ticked when the dialog opens, and while it is ticked Duration and Time between matches are both greyed out. A football group has no rounds, so leaving it ticked puts every fixture in the group on the same kick-off time.

Each kick-off is the one before it plus the duration plus the gap. A 15-minute match with a 20-minute gap puts 35 minutes between kick-offs: 10:00, then 10:35, then 11:10.

You do not have to fill everything in. Only the fields you set are applied, so you can move a group to a new date and leave its times alone.

Your fixtures sit under a WEEK heading. The Schedule tab groups a football group by week. A group whose fixtures all fall in one week shows a single WEEK 1 band above them.

A fixture with no date sits under UNSCHEDULED. That band is the last one, under the weeks. It appears only when a fixture is in it, and a fixture there reads Incomplete until it is given a date. See "Rescheduling fixtures, and rolling them onto the next day" for how a fixture gets there.