Either way: Discovery starts shooting in April. Even if season 2 won't take 10 months, but let's say 7 or 8 months... (which I doubt), but even so: I don't think FX will wait for Doug Jones to be finished filming Star Trek for him to join the rest of the cast of this new comedy series... You can't be a series regular in Star Trek and also have enough time to be a recurring character on another show. Not when Star Trek takes at least 8 months to film a season...