Bit of a convoluted title but basically I installed beta 3 on my 950XL but couldn't unlock the key chain from Dropbox (historic old version password problem I read about here), so I changed the password on another device and all good.
However, I then changed the password back to what it was (on another device) and the app on my 950XL wouldn't open without the first changed password. Once open I thought ok, let's change the password back to the original here. Unfortunately something went wrong and whilst the password for my vault is fine on other devices, set to my original password, I can't open 1password on my 950XL. All I'm presented with on launching the app is the enter password screen. Reboots, uninstalls/reinstalls have no affect, it always opens on the password screen (where neither password, original or changed, work) I can't seem to clear out it's memory of the old vault, nor open a new vault.