I asked them before swapping out my stereo and the gal asked her supervisor. She then told me to activate my free subscription first then do the transfer. I activated the 1 year service on the spot. A couple of weeks later, I replace my stereo and called them. A guy answered and said I couldn't transfer it, because the 1 year free is only for the factory radio due to Dodge wanting me to keep it. I said he was full of bull, because Dodge already has my money for their factory radio. Sirius was the only one to gain, which is why Sirius made the deal with Dodge. I then said if he didn't transfer it, they would lose me forever. I argued back and forth with him telling him of my previous call. He asked his supervisor and reluctantly transferred it.
It really depends on who is on the other end of the line with Sirius.
Mark H