Sounds like a Bradley Smoker (they use "biscuits") which are a pressed disc that it uses for heat/smoke/etc.
I haven't heard much good about them. Not really much bad, just no comment from most folks. Mainly you have to buy their biscuits for their unit and not use regular wood.
How long for a brined/12# bird?
The recipe you refer to says 1.25 to 1.5 hours per pound. One reason is the low temperature. I don't know why, but a lot of the older recipes (old, like 4 to 5 years only) use that temp range. In fact, CS has 180 as the brisket pre-set.
I use 250 (or 300 in my larger CS) and it will take half the time.
I did a 22# for Christmas, it was done in 6.5 hours. Brined birds will cook faster.
For a rule of thumb, with a temp of 250, I use 30 min a pound. So, with brining, I'd say just under 6 hours.
Now go get your CS and you'll be happy. But you welcome in the forum, Regardless of your smoker. We'll just make you jealous with our success.
Smokin'