Couple weeks ago, I also had a publix receipt "pending." I thought maybe it happens if a large number of people are submitting at once and basically overloads the system.
In the past, I have always had to scan the UPC for every Ibotta item on a Publix receipt.
I have noticed that the last few receipts from Publix - Ibotta has actually found the right items and I didn't have to scan the UPCs at all.
When I had to scan a UPC, the Publix receipt would take a few hours to process. When the app finds the items on its own, my receipts go through faster.
But it doesn't surprise me if Publix takes a few hours or over night.
I am guessing your receipts have processed quicker than mine. Maybe because you are closer to Denver. 😃