I understand what you’re saying. But the BT Cloud worked fine on my old iPhone 5S - iOS 12 unobtrusive in the background. No need to visit it from time to time. So when Apple released iOS 13 and 14 it sounds like there were fundamental changes to how Apps like BT Cloud operated within it. And if that is the case why were App developers caught off-guard? Sounds like it caused issues with BT Cloud on Macs too.
Just to say that BTCloud on my iPhone iOS 14.x has been syncing reliably and reasonably fast for the last month or so. I have now closed my original complaint. The issues around the constant flicking through of existing - previously backed up - content before backing up the recent stuff, seems to have been sorted. There are occasions when I’ve gone to the Home page on the app and it hadn’t yet backed up the day’s new content. But that’s probably because the phone hadn’t been moved. BT are saying that server performance will be improved in the near future - which should speed up the backing up even more - but couldn’t give a date. Judging by posts elsewhere it would seem there are other Cloud issues occupying their minds.