According to this Thread there should be a new only option, as I am still awaiting the 4.39 software update I can't confirm one way or another, it may be a good idea to restart your box try turning it off with the switch on the back of the box, leave it for a couple of minutes then turn it back on, you could also try doing a factory reset if turning the power off + on makes difference to your advanced recording options, if you do the factory reset just select the option to keep your recordings, you will have to sign in again to iPlayer and other apps like Netflix, and reset your Dolby setting if you have changed it from the default always convert.