Version 220.127.116.11 brought a major change to how Heal Groups and Frames work.
Version 18.104.22.168 updates the way Vehicles and Pets groups work in Frames.
Groups Vehicle, Pets, Targets, Focus and Enemy are fixed to positions 7, 8, 9, 10 and 11
Vehicle and Pets have their own individual frame (last in the list) but can also be placed in frames available to other groups.
Target, Focus and Enemy have their own individual frame and no other options.
With Vehicle and Pets: In large raids, it is recommend to use their own individual frames.