Believe or not the OT and A4 have all the same scales as the Digitone. It’s a music theory thing. Any major or minor scale is actually the same notes as 6 other modal scales in different keys… The only thing needed to be updated in the OT and A4 would be the UI to allow you to select them by the proper key and name.
Using the following chart you can access the 6 other modes in any key by setting the OT arp to the corresponding relative major scale and key.