Just had a power cut (70 minutes not too bad a fix time for an 11kV
fault I suppose)

OK, I did have to get up to silence the UPS (also shut down a couple of
unnecessary PCs while at it to extend runtime)

But most annoying is the 15 minutes of alarms sounding due to failed
batteries, then sounding again for another 15 minutes when the power
comes back ...

People seem to think this is normal/acceptable ...