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In iOS 12 the initial estimate shows mostly System while it searches. Leave it on that screen and you may find that figure changes.
 
In iOS 12 the initial estimate shows mostly System while it searches. Leave it on that screen and you may find that figure changes.
You’re absolutely right it has reduced over the last few hrs although it seems to have settled at 39GB for me which is still an awful lot. Ideally I’d try to clean install with a restore to try and fix this but I don’t see an easy way to do this on the iOS 12 Public Beta.
 
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