Some blocks have a time that is not yours to move. The CEO can take questions from 10:00 to 11:00 and not a minute later; lunch is booked with the venue for 12:30. A lock pins that block to its start time. When you edit the start time of an earlier block, the change ripples forward through the blocks that follow, and the ripple stops at the first locked block: the locked block keeps its time, and so does everything after it.

A lock is a constraint, not a magnet. It never moves other blocks to make room for the locked one. If an earlier block now runs into it, you see an overlap warning and decide yourself what to shorten.

Steps

Open the agenda in the builder and find the block that has a fixed time.
Set its start time first. Click the time in the left column of the block row, type the new time (for example 10:00) and press Enter.
Hover over the row. A small open-padlock icon appears to the left of the start time. Its tooltip reads Lock start time (keep this exact time).
Click the padlock. It turns blue and closed, and the block is now locked at that time. On a phone, the same padlock sits in the time strip at the top of the block sheet.
To release it later, click the padlock again. The tooltip now reads Unlock start time (return to auto-calculated).

Typing a start time does not lock a block. A time you type is a starting point that later edits can push around; only the padlock makes it fixed. The two are separate on purpose, so you can retime an agenda freely and lock only the handful of moments that are truly fixed.

What a lock changes

When a block before the lock changes its start time, the blocks between the two shift by the same number of minutes. The locked block and every block after it stay exactly where they were. If the shift eats the room before the locked block, a red overlap warning appears between the two, telling you how many minutes collide and asking you to Adjust block durations to resolve. The usual Push next blocks later control is not offered there, because pushing would move the locked block.

If the shift instead opens a gap before the locked block, Close gap is still available. It pulls the locked block earlier and carries the lock with it, and its tooltip warns you first: Next block is locked — closing the gap moves it earlier.

Wrapper blocks (Group Work, Breakout, Stations) can be locked like any other block. The activities inside them cannot, because their times are derived from the wrapper's start time and run back to back inside it.

Tip: If you draft the agenda with AI and mention the constraint in the brief ("the CEO is only available 10–11"), the draft arrives with that block already locked. Moving a block to Standby or duplicating it removes the lock.

What to do next

For how start times, durations, gaps and the ripple behave in general, read Blocks, days and start times.