Awful standby time on iPad Pro M5?

I’ve recently picked up an iPad Pro M5 11” 512GB. I was under the impression that iPads have incredible standby time, like you can leave it a couple weeks and it’ll still hold a good charge, but for some reason that’s not been my experience? It was fully charged at around 8am yesterday, I unplugged it, put it on airplane mode and left it locked and unused for the last 24 hours and it’s dropped down to 74% already???? So even on airplane mode it’ll be totally dead in 4 days of doing absolutely nothing?????

Is anyone else experiencing this? Is this normal and I’m mistaken? Is it an iPadOS 26 issue?