Would the existing backdoor lock via KUAL work on a 5.4.0 PW2? I normally keep the wifi off anyway, but I quite like to have the safety net of BDL on my device.
I would offer to try but I really, really don't want to run he risk of my PW2 updating to 5.4.2 given the mess it creates with cloud collections and as far as I'm aware there's then no way of going back to 5.4.0
