Nooo, do not change any feedback now, and there will be nothing to enforce your seller to refund you in January as you will exceeded eBay's 30 day timeframe.
Listen to the seller no more, but contact Customer Services explain the issue with the label, they should send the appropriate one or see what they suggest.
Also, do not close the case early for any excuse or promise the seller may give.
I strongly recommend contacting CS 8 a.m. on a weekday when the lines open for ' live agents' as then, there's more chance of Dublin answering.
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.
It's not easy to get through to CS, you just have to have perseverance! Instead of a quick option, 'Contact Us' which put you direct to a CS agent, you have to scroll past ' How Can We Help you today, to the very bottom and click on the Contact Us below Need More Help?
That takes you to an annoying AI bot but if you persevere keep asking questions it cannot answer and Insist on an agent, they do finally put you through and say .... waiting time ** minutes!
@chiltercarcompany