All batteries should be shipped between 3.7 and 3.8 volts per cell. If they were higher than that, then you purchased returned batteries that they are trying to pass as new and the previous owner charged the pack before shipping back. And as always, you should store your batteries at a storage charge.
IMO, if the batteries have a decent internal resistance, you should be fine. But that decision is up to you.
I would still send the seller an email asking why they are at 4V.