That is correct

You are seen as a new seller by eBay, and as such, like everyone, your funds will be on hold for 30 days

Unlikely one positive feedback will get your funds released early, but you could contact eBay and you might get very very lucky

Hopefully you read up on all the other changes that have happened since you last sold something

There have been a lot, and if you were not expecting your funds would be held (as they would have been even if you posted the item with tracking), you'll need to make sure there is nothing else you missed