Thanks for the advice, yeah I was going to remind them about it only being a side to side tire rotation. As I am still on the stock tires, I was planning to ride them out for the next 5-6 months or so and then perhaps upgrade to better tires/195s all around like some here have done. From that point, would it then be a regular front to back rotation?
As for the 4G upgrade, I am not sure how it works in the US, but here in Canada, OnStar has been operating on the now-ancient (and decommissioned - that is the problem!) 2G network. Of course, the 2015+ vehicles generally come with 4G onboard, but the older ones do not. So over the last couple of years, GM has been transitioning customers to the 4G network via a free upgrade, so that they can continue their OnStar service. I actually got the letter offering the upgrade last summer or so, but I just put it off.
I actually have the premium OnStar package including navigation that was already included (prepaid) with the car when I bought it, but I never really use it (it is still valid for another year). After that, I can choose to continue with the same package (paid), downgrade to a lower package (paid), or just go with the basic service, which is really just app functionality and is provided by GM for about 5 years without charge. This is really what use day-to-day, but I have noticed that it does take a while for the app to refresh with data, most likely due to the slow 2G network. So the bottom line of this upgrade to me is just that I will hopefully see a faster refresh of data in the app, that's about it.