I'm using an iPhone 6s+ with 128 GB internal storage. It was running on iOS 12.4.1 up until recently when I've decided to update iOS to the suggested 14.1.7. Prior to updating, I've created a backup which is about 116 GB in size (yes, my storage was pretty full).
Now here's the problem: after updating iOS, I can't restore my backup onto the phone because iTunes says there is not enough space on the phone.
What I've tried:
- trying out different softwares to delete chunks of data ouf of the backup so it becomes smaller in size: none of them worked.
- downgrading iOS: doesn't work because the old iOS is no longer signed.
- reverting to factory new state: this also didn't downgrade the iOS it seems. After immediately reverting, the backup actually started loading back onto the phone, only to abort at 99% and returning the same error about having not enough space.
How can I now get my backup (or parts of it) back onto the phone if the new firmware takes up more space and I can't downgrade iOS or "edit" the backup?