You should not have to handle a claim for damaged items if you used Simple Delivery - this is from the original email Ebay sent all sellers on 31st March: 'Full protection: Enjoy peace of mind with eBay's full coverage for items lost or damaged in transit, where we handle claims with buyers so you don’t have to. '
If you are being asked to refund for an item damaged in transit, contact Customer Services.
At the moment, it is uncertain what will happen with overpaid postage. The buyer pays Ebay direct for postage so Ebay should refund the buyer. However, it is very early days and Simple Delivery is not yet mandatory so that may be a detail that needs to be sorted. Sellers have not been able to send invoices to combine postage for several weeks now - it is a known issue and a real problem for sellers and buyers.
Most genuine private sellers who are selling their own personal possessions would not have the option of replacing an item and the buyer would have to be refunded - by Ebay if an item was damaged in transit.
However, if you were trading correctly and had a business account you would not have to use Simple Delivery or wait for payment until after delivery. If you make items to sell, or buy items to sell you do need to upgrade to a business account.
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)
