I remember in order to justify the Brint to Brienne thing in world I played a very convoluted route where I basically set it up so that I rushed to the armor at the start, and then by the time I arrived back in Hawkethorne, Dog Days would trigger and hey Garth's son is in danger you can't postpone that! So I'd go do Dog Days instead of heading to Sanders to purify the armor, and even when I had to go get Sanders to talk to Hethia, hey the loggers and Garret are still locked up you gotta go go go, and by the time I got back the time on the armor should have run out.
It doesn't actually run out because the game has a few artificial stopping points, presumably to give players plenty of chances to change their mind or remember that's an option, but at that point it's game mechanics so I call it a day.