Those are just eBay's estimates, and a tad optimistic, always best to wait a couple more days as post is not exactly reliable or exact, either !
Is there any tracking on the order details? You could check the courier's website to see the item's progress.
If it doesn't arrive in Monday's post proceed this way :
If you are not fully refunded within 3 days, you must escalate the case on day 4 or within 30 days from opening the case, and eBay will step in and force the refund.
Do not close the case early for any excuse or promise the seller may give, and do not forget to escalate.
@paad_672
