Tempo change - simple question

I’ve placed a number of regions on 3 or 4 tracks snaping to grid, and now want to change the
tempo. I edit the tempo marker and the grid changes, but all my regions stay in the
same place (ie; the regions that we’re snapped to bar 1, bar 3, etc do not stick with the
bars after the tempo change, instead, they appear to stay at the same time).

How can I effect this?

Thanks so much - I feel ridiculous for not seeing that.

@bzImage: in ardour, audio regions are not “glued” to Bars|beats (musical time) by default. You have to right click on regions you want to to behave in this way, and select “Glue to bars and beats” from the region’s context menu.