Going back to older version

Going back to older version

Hi,

One of our tech did a new version of our app, but created problems that we do not have time to repair, we just want to go back to an older version for the moment. To make sure we choose the right older version, we also want to double-check the dates of the various versions.

How do we do that   (checking the date and making the switch) ?

And will we loose the new version that needs improvement ?

Sylvain