Mmm, that is a bit odd.
Those dates for delivery are just eBay's estimates, so worth waiting a few days past the last estimated date for delivery. If the item does not arrive open a case for item not received, and escalate on day 4 if not refunded beforehand.
If there is an issue receiving a full refund which you are entitled to, because strangely a partial refund has already been made, then contact eBay Customer Services, and inform them what has happened here.
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 8 a.m. - 10 p.m. on weekdays
9 a.m. - 6 p.m. on weekends.
Automated agents will be available on chat outside of the above hours.
I recommend contacting CS first thing in the morning as there's more chance of Dublin answering.
@diytoolbox