Until the shingles are installed, there should be some movement of air/moisture out from under the shingles. You'd be surprised at the way things like air and moisture can 'relieve' themselves.
And as Dodgeman said, the water didn't have enough time to 'sit' to really soak the sheathing. Moisture is OK. Your house will be 'breathing' that out all the time.
My best to ya and hope this helps.
Jay J -Moderator
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