Anytime Trostani Discordant is played, if there are Lifelink Soldier tokens in play, it buffs them twice. Any other creatures, tokens or otherwise, receive the +X/+X the one time, while the Lifelink Soldiers receive it twice.
Hi Brakkis, thank you for reporting this. I’ve confirmed with the team that they are currently aware of this issue. I’ll add this to the bug list for reference.