We saw on Github that the maximum robot volume for open will decrease from 22 x 22 to 20 x 20.
Will the same thing happen in LWL?
The plan for 2021 is indeed to decrease the diameter/height to 20cm in Open (see the fourth note on the 19th page in the draft rules. Lightweight should stay the same for the time being, but this may be revisited in the future.
Feel free to let me know if you have any other questions.