It shouldn't be surprising
It shouldn't be surprising with the steep hike in nickel prices that Tesla will use the Chinese LFP battery pack in the upcoming Model Y SR. Elon Musk said that all SR models would use LFP batteries. He didn't build the previously announced Model Y SR/RWD, but he can just have Giga Shanghai ship of the Model Y LFP battery packs, just as they do now for the Model 3 SR today. I think that (for the moment) they will probably use the new 4680 batteries solely in the Model Y, Performance for this year.