It's not an issue to me, since I only use it as a USB device (Linux user). But I, too, do not have the option anymore, so maybe my information can be of help to others.
- Have an SP
- First with the not final 2.004.6 (had plenty of upgrades before that as well). Don't know if the option was still there or not.
- Then the official 2.004.6, which b0rked my M6 (first time ever), but I got it back working with DFUTools with 2.004.6 straight away.