Simple Question Using CDJ for RekordBox and CDs

Simple question but I don't have CDJs at home so can't test it out, i just use them in clubs.

I DJ back2back with a friend and we have always used CDs but he's just got record box so next time i will be using CDs and him Rekord box on a USB.

Now i know you can switch from either option on the deck but what i want to know is...

If you have the decks linked up and the current tune is playing on the slave deck and i want to play a CD on the master deck.

If i change the main deck to "Disc" will it stop the slave deck playing from record box USB as well?

Hope that makes sense.

Thank you.