To pour some salt: I am afraid your 'all telephony functions disabled' will pop up more often and stay...
I had 4 devices dieing this death and as I 'needed' WhatsThat always used a Jolla as secondary device.

Now after the last death in April (or so) I switched this month to a XA2 (not the XA2+ which is still in my drawer) and I can't get no satisfaction!

So if you are still happy with what N900 can offer to you nowadays (HW spec, display size, SSL issues...): get a cheap one from the bay and use backupmenu. You will be more happy!!!
Else ........ idk