Allow users to append a group at the end of the /lp user promote command:
/lp user {name} promote {track} {final-group}

If the track is laid out like: default->vip->donor->staff and I do /lp user {name} promote track1 donor.

If the user was in the group default, it would be cool if they moved through VIP and on to donor in one command.

/lp user <user> parent set <group> and /lp user <user> parent add <group> exist for that.
The promotion-command is for promoting a user across a track. Everything else can/should be handled by the above commands.

You can already do that: https://github.com/lucko/LuckPerms/wiki/Command-Usage:-Parent#lp-usergroup-usergroup-parent-settrack-track-group-context

Thank you Brian that should work for what I need 👍