I get a message from him complaining about damages to the items

I have a buyer that purchased something back in April and was delivered back on April 10th (he paid for parcel and I upgraded him to priority free of charge). I hadn't heard anything from him so I just assumed everything was fine.

Fast forward to today, I get a message from him complaining about damages to the items. It's been over a month since it was delivered. I told him I'm happy to provide a full refund upon return or we can try to file a claim (since it had the free priority insurance on it) but I wasn't sure with how long ago it was delivered if a claim would even be okay to do.

Is this the correct recourse? I know there's like, a million questions/issues going on with the new defect system. I don't have a lot of defects so if I need to have the items returned, it's not TOO big of a thing but I just find it weird it's taken him over a month to look these things over.That is about the best you can do so far.

But with the amount of time that has passed since it was delivered, you might want to ask the buyer what country they are in and did they use a reshipper.  Reshippers are notorious for repacking items and they can get damaged that way.  On the plus side for you, the buyer loses buyer protection when the items are shipped out of the country.  Did you ship to Kentucky, you might be in ebay's Global Shipping Program and not know it.

And why didn't you just hop in the TARDIS and deliver it yourself?