Had mine MYP for 8 month and the rated range never went anywhere near 305 - always hovered around 265-275ish. I always charge it to 80% on a daily basis. Do you think I need to have the service center take a look at the battery health?
Talk to Tesla once you drop below about 204 rated miles (wasn't 291 the max rated range? I guess it's not clear whether you had the 82kWh pack or not, but probably not, so not clear what your 100% was, and I don't know whether a software update changed the constant from the initial (77.8kWh/291mile) value at some point). Sounds to me like you got a bad pack, but it is what it is.
Easy to verify - drive the car
continuously (no stopping!!!) from 100% to 10% or so, and use the formula TripEnergy/0.9/0.99/0.955 = Pack Capacity. Probably around 71kWh for you, if you should have been at 77.8kWh originally.
See whether the range at 100% adjusts. You can also see whether the energy screen calculation adjusts.
I am pretty skeptical of the claims that this is BMS miscalibration. However, it DOES happen (rarely!). You can do the steps to ensure your car sleeps (must turn off Sentry, etc.), at a variety of SOCs, but I doubt it will do much unless you have very unusual use patterns and never drop below 60% SoC or something.
Of course, the BMS can be off by a couple kWh, that's common (5-10 rated miles). But this sort of discrepancy you are seeing is unlikely to be simply a misestimation. And occasionally Tesla seems to change the software and that can cause shifts in the estimate (seems less common these days since I think they understand the pack's voltage & temperature characteristics better now?).
Try the steps recommended (drain pack, let it sleep, charge it up to a lower SOC, let it sleep, exercise a different SOC range, etc., etc.), but I wouldn't hold your breath.
But, DO report back after you try these things. Sleeping is obvious - you'll hear the contactors closing routinely when you get to your car, and the app response will become routinely sluggish. If you don't see/hear these behaviors, you need to change your car configuration to ensure it is sleeping. But again, don't hold your breath. The BMS needs to have a decent idea of remaining energy, whether it is allowed to sleep or not.
The good news is that the 9% capacity loss you are seeing is fairly common. The unusual thing about your situation is that you apparently
started there, so I worry about the prospects for you a year or two for now. Keep us posted. No reason to contact Tesla until about 205 miles at a full charge.
