I'd say your logic is flawed. If there are 1000 commands in the company and you increase that to 1100 commands due to long haul expansion then yes, 100 people get their commands quicker (but only by the amount of time it would have taken for 100 of the original 1000 to retire). Once the commands have stabilised at 1100, you are then at exactly the same time to command again, because you still have to wait for people to retire
Actually I'd say my logic is not flawed as by your reasoning everyone waiting for command is 100 places closer than they would be otherwise. Only the 101th recruit and greater after the expansion will be back to the same timescales of waiting for retirements. 100 people cannot shuffle up the seniority in isolation. As for the bmi bubble lower down it is ostensibly a closed system except for the ones whose doj is after.