Most guilds running ROTE probably aren't single phasing Tatooine in the phase they unlock it anyway, so I'd argue that this change is more detrimental than just leaving Fifth Brother in that slot. You preload a Fifth Brother into operations while you complete another planet and then finish ops the next phase with everyone having him available to use in the mission.
It's just a bad change overall. Again, I'm just asking that they put more thought into who they choose for these replacement characters when the players are not at fault for a mistake the devs originally made.