I have heard that some ebay vendors WAIT til your payment actually clears and is in their bank. What payments are the type that take longer to clear and show up in their bank: Paypal payments where the funds come from a checking or savings account instead of a (instant) credit card. The Paypal payment that comes from a checking account is looked at as an E-check. That is what an ebay vendor told me. BUT, that said, some ebay vendors will ship same day regardless.
Yes, that's true -- in fact, the seller is NOT protected unless they do wait for payment to clear.
Seller protection is slim compared to buyer protection (don't get me started on 'not as described' which can include all sorts of imaginary and far-reaching assumptions on the part of a buyer), so I'd be surprised to see folks shipping before funds are released.
Ann - recently retired 3+ year ebay seller of non-knitting items