Hi Peter, i have just got this message on my ipad as my full backup almost completes.
I have enough memory on board this use to be a problem before so i hope it can be resolved easily, i have the latest updates on everything.IOS 16.3.1 ST3 3.6.10.
Cheers Damir

Just now i managed to complete my backup by restarting my ipad and unplugging it from my imac , restarting my imac, then the backup process worked to the end as normal, what caused it and what fixed it is a mystery, hopefully it wont happen again next time i do a backup.
I think having it cable connected to the imac might be the reason but i will keep an eye on this .
Cheers Damir