Sub-items available, but not for the whole account?

So I seem to suddenly have sub-items as an Alpha feature in the monday.labs area.
I have enabled them excitedly and started using them on a board.
But for some reason I am the only one who can see them???

How can I let my entire team see the sub-items?

Have your team members refreshed their browsers?

Yes, and they logged out and back in, too.
Now they can create their own sub-items on the board (which results in a new sub-items column, which then everybody sees), but they still won’t see mine.

I now deleted the subitems column and have to create all the subitems I had in there.
But at least now the whole team sees them.

Seems to be a bug