Royal Mail's tracking is sometimes not in sync with eBay's tracking, and the latter is the most important for releasing a faster payout, that is, 2 days after the delivery date.
If you have found your tracking has not updated, therefore holding back your payout, contact eBay Customer Services, provide the tracking showing delivery, ask if they can kindly release your payout now as 48 hours have passed the delivery date. Now, they used to do this, not sure if they still can, but worth asking.
If they cannot it's a minimum wait of 14 days for the release of the payout.
This is the easiest and quickest way to contact eBay Customer Services, for a Call Back option.
https://www.ebay.co.uk/help/eua?id=5275&mkevt=1&mkpid
Lines open between 8 a.m. to 10 p.m. on weekdays.
9 a.m. to 6 p.m. on weekends.
I recommend contacting CS very first thing in the morning, when the lines first open, as there's more chance of Dublin answering.
@scottspine
