Nobody in the forum will have a real answer to that question.
I do sympathise.
The last time I had a return, the buyer had about 10 working days to send the item back.
Once I had it back, I had precisely 48 hours (from the minute tracking showed it had been delivered) to refund the buyer.
There does seem to be an imbalance between how Ebay treat buyers and sellers.
"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)