the temp swings when you open it
If you are talking about a temperature overshoot -- like maybe both at start up and after opening the lid for a bit -- I have exercised that daemon on my 590 by adjusting the "Minimum Feed Rate (MFR)" in the advanced setting on the app to a lower percentage.
I'll bet your MFR was set by default to 3.5% (that's a percentage of maximum feed I believe). I've found that is too high.
It's a strange concept for some, but the grill has to be able to bleed off some heat. The trouble is after a typical startup or trying to reach you "set temp" again after opening the lid, the grill is going to burn hot and fast. As it approaches set temp, it slows down, but not fast enough to stop right at set temp.
Then, when it goes above set temp, it still has to keep the fire going, but it want to cool at the same time, so it drops down to MFR. That obviously still generates a certain amount of heat. If the MFR is too high, it will generate more heat than it can dissipate. Too low of an MFR can allow the fire to go out and will cause some extra fluctuation around set temp due to the nature of the PID controller.
I set mine to 2% and have used 2.5% depending on the pellets. Some pellets, like mesquite, burn hotter. You are probably familiar with that with your offset stick burner.
Anyway, that is what I found solves the overshooting of temperature and helps the grill maintain a lower setting on warm days as well.
I have used the sear kit and also a flat cast iron griddle type pan in my grills for searing steak and crisping up chicken. I like the reverse sear method for steaks. I smoke them until they are within 15 degrees of temp, take them off, raise the temp to 350, 400; whatever you like for searing... then four minutes a side or so as you probably typically do. I like getting the best of both worlds -- smokey flavor and a sear.
Have fun with it, good luck, and welcome!
