BA command time can be a matter of luck and timing. Fleets and bases may be unpopular and then there is a change, usually for financial reasons when there is restructuring.
EOG was like this for a while: command time could be as little as a year from joining BA. Those who wanted an early command went for it and are probably very glad they did, now that there is a much longer wait.
So, if you are thinking of joining as a DEP from another airline, go for it! First officers get treated much better than in many other outfits, that's for sure. Things like being able to taxi the aeroplane, and a complete reversal of roles when it is your leg. You are also treated like a sentient being, instead of a rather thick dog, as happens outside BA (not in all airlines, but certainly in some). Everything is fair, too. No Mr Nastys in the sim making up silly scenarios or putting the pressure on just for the fun of it. BA's training is second to none.
Good luck!
