I keep getting warnings that my icloud space is almost full, but I have almost 1GB left
I recently upgraded my iPhone 4S to iOS 8, then a couple of days later got an iPhone 6 (obviously with iOS 8), 64GB. I've removed the backups from my old phone, so in my iCloud, it's telling me there's a backup for my iPad of around 800MB and my (new) iPhone of around 3.2GB. All this seems right (it's mostly photos). I am now getting periodic pop-up warnings from iCloud (running on Windows 7 64-bit Pro) that say "iCloud storage almost full". It's showing that I have about 975MB free which while not a lot, is sufficient since each backup should continue to be around the same size.
The thing that's annoying is that I seem to be getting this warning pretty frequently. I haven't timed it, but it seems like these warnings are happening every 10 or 15 minutes. Is there some threshold of free space that I need to maintain to prevent these warnings?
Would deleting my backup and creating a new one help?
iPhone 6, iOS 8