Partial blackout story (not UPS, though)
Just a week ago Sunday, while driving from home to church to play drums -- a distance of only 3 miles -- the missus called and said there were power issues at home just after I left but after a few flicks up & down it stabilized.
But the church building was a different story. I walk in to the sanctuary where only half the lights are working and all the outlets on the stage-left side* are dead. This included the remote audio I/O unit that connects to the main PA board by Ethernet (Allen & Heath system), the PoE that runs two A&H personal-monitor units (one is mine), the Roland digital drums I play (but the church owns them), the Hammond organ, and all the musician's powered monitor speakers, plus the main monitors at stage front.
And on top of that many of the HVAC units were dead, so the environment was not horrible but temperature was slowly climbing; the building's internet was also gone so the Facebook livestream was in question.
This being the first Sunday we were trying two services to keep attendance down and social distance up, this was NOT a good omen overall. (The livestream was going to use the second service.)
Lighting aside, the main A/V booth survived -- graphics computer, audio, and main speaker amps -- as did the large flat-screens (two for the congregants and one in the back for the praise team). We lost organ, drums, and audio interface to the separate digital keyboard, but still had piano (direct-wired mic), guitar (wireless pickup to the main board), horns, and my personal pair of bongos and were a little more "unplugged" for the 9:00.
Seeing as the outlets actually on stage were working, which are only occasionally used for LED PAR wall-wash lights, someone grabbed some extension cords and we got the drums, monitors and audio/PoE units working again just before the second service. They still did the livestream, probably by turning on tethering on someone's phone; I heard from the missus that the feed wasn't as stable.
Here's what really happened: the building has a 3-phase utility connection at the main road; different parts of the building tap into different phases. The power flicks** took out 1 phase blew the fuse on the roadside utility pole. Thankfully we have a congregant sparky (electrician) who quickly diagnosed it and helped turn off any 3-phase loads (like the HVAC) quickly. (I think they tried some cross-over switches trying to restore the dead circuits by tying them to a working phase, but that kept tripping also.) In the end, nothing in the building was harmed and it was all-systems-normal when I was there Thursday evening for practice.
* Yes, I worked it to say "left side" as an allusion to Marvin and you found it. Pat yourself on the back, you nerd.
** I was also watching our utility's outage reports via their own app. I think there was an issue with a substation very close to home and it took out some nearby neighborhoods completely. Wouldn't have been the first time. I blame the squirrels.