now had a 5:41am email from Royal Mail claiming it will be delivered tomorrow lunchtime; but that was followed by a 9:44am email claiming it would be delivered today instead (possibly quite soon).
finally received the package - after a lot more false alarms - and turned the detector part of the doorbell off again (to save its battery as well as stopping the nuisance alerts).
this is all very mysterious. If it doesn't work this time, maybe I could come down and have a go at fixing it? I'd have to dress up in some kind of PPE I guess.
also why the new ones don't work for ethernet connection. The WOC techy had vague recollections that there had been some sort of change in protocol etc in recent years but was unable to specify what it was!