Giant 8m baby in size 6 diapers HELP

A

Bb is 30” tall and just has a long thick torso (she wears 18-24m clothes). We do elimination communication but I still have her in diapers in between potty breaks and I don’t foresee her being able to move on to Pull-Ups for awhile because she doesn’t have the gross motor skills to do that BUT she’s already in the largest size diaper what gives???