You are a new seller who has sold an expensive item so Ebay will hold your funds until your account has been verified.
If your buyer starts a return, you will have to refund them - that is not what the BPF is for.
Established sellers with verified bank accounts don't have to wait for thei funds.
"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)