When a league ends, the characters and the stash tabs are merged in the parent league (either SC/HC). The stash tabs are then made "pick-only", i.e. a person cannot put anything in those tabs, only take away, and they disappear when empty.
Is there a time limit after which they will disappear even if there are items into them?
21 Answer
On the Official PoE Wiki it says that
Tabs from the temporary league will appear as remove-only tabs in the parent league. These tabs will remain indefinitely, but items cannot be put into them, even items which started out in that tab. Once a remove-only tab has been emptied, it will disappear.
