From my experience, I purchased a new (to me) Remington 700 SPS 308 in the box back in December.
Knowing about the recall, I went online to the Remington site and went through the process of registering the rifle under my name.
There is a part of that registration that allows you to ask that question online.
You will obviously need the serial number from your rifle to go through the registration and determination if your specific rifle is subject to this recall.
My rifle was subject to the recall and I forwarded mine to Gravel Agency in Quebec after receiving directions, the shipping box and postage to get it to them.
Turnaround time was amazing, even over the holiday period it took but a couple of weeks.
Conversely, you could contact the Gravel Agency direct to find out the best way to do this.
Good luck...
...B