I'd say that given the change in production to J-20A the yearly production rate cannot be stated with any real degree of confidence. I wouldn't be surprised with anything from 25 to 125. As for the total number in service, we have a bit more clarity there, it's almost certainly more than 300 and I'd say it's very likely to be at least 350 by now.
This post by Deino is a bit outdated, in this thread we have received confirmation that a number of the units listed there has been confirmed to be operated J-20 now. This includes
19th,
131st,
2nd, and I believe that 55th was also confirmed at some point? There are also additional AB that are now confirmed or rumored including
21st, and
41st as well as the first J-20A unit now forming which would entail the transfer of at least some of their J-20 to a different unit.
So if we wrap everything up and include the FTTB, there should be at least 350ish J-20 in service and given that our rumor/confirmation is usually delayed by at least a little and sometimes by 6 months or more it's not unreasonable to think it's somewhere around 400 now. Anything significantly higher than that I think is unlikely, especially in light of the change in production to J-20A.