eBay item purchased April 8, tracking number Apr 16, Post office still waiting for item

[Gareth]

Sometimes, the post office forgets to scan an item upon receipt. I had a recent package that never got scanned until it was out for delivery. You’re not at risk of missing opening a case, so you could wait a few days, but you’re likely eligible to open one now (I did for my package). Since it takes a few days before you can close a case, I like to open them ASAP. When my package showed up, I let the case close in the seller’s favor.

If you’re dealing with a power seller, opening a case might give you extra leverage since apparently they need to close them within a certain timeframe to keep their status (according to another seller I had a case open with).