Saw that, but my iPad Mini2 is way too old to have any updates, so I ignored it…
I’m still amazed this kind of thing happens. Apple is a multi trillion dollar company for friggin’ sake. Just how poor is their stability stress testing?
And this is why I never install whole number updates and always wait for the first X.Y release.
All I can think of is that the error was triggered by some unusual, unexpected action, or some app interaction they missed in the presaging… The whiz kids are on it! 
The level of hardware, coding is way beyond me, I only fiddles a little in 6502 code, Basic, and a little Unix at work, chasing what was generally mechanical of man-made errors, but sometimes, the coding needed patches… Support & original folks were handy, focussed in specific areas of the code, so, stuff can happen…
Didn’t seem to bother today’s market…
Yeah, it was apparently due to a specific sequence of prior iOS installs.
Still, Apple should be able to test for this. The article said:
Not all M4 ‌iPad Pro‌ owners have had an issue installing the update, and it could be linked to installing the new iOS 17.7 update before installing iOS 18. Apple will make the software available again when the underlying problem has been addressed.
The Market wouldn’t care about a tiny issue like this. It’s not at all like the reaction that the news that “Apple Intelligence Found to be a Chinese Trojan Horse!” would cause 