Cannot update to 4.4.0.58 (Xperia X): "Problem with store. Unable to determine update size"

General
9

Did you read https://forum.sailfishos.org/t/solved-xperia-x-4-3-0-15-upgrade-to-4-4-0-58-failed/?

In my case post_sfos-upgrade, part of sfos-upgrade, seemed to do some tricks.