I have charged to 90% one time after receiving 2020.12.11.1. The same 277/278 miles I got before this, going back at least to 2019.32.11.1. This translates to about 308 miles. 2018 LR RWD.
I did get the mileage boost to ~325 when it first appeared but then reverted back to 310/311 a month or two later.