I just purchased AR3 robot kits and stepperonline motors on Jan 22 and @Chris Annin releases today, Feb 6, the AR4 version. This is a great project and I'll just have to read/study and upgrade the changes which fortunately look minimal (I missed the new electrical kit Chris already prepared now).
Last Thursday I purchased a Creality Ender-3 S1 that finally is giving me great printed pieces. Okay, start the changes ... :)
Thank you very much, Chris and all posters and Youtubers that have shared their builds.
It wont take much to build the AR4. The motors and encoders you purchases for the AR3 will still work with the AR4 - I will post an updated sketch in the AR3 downloads in the next day or two for using the AR3 dual shaft motors / CUI encoders with the AR4 software.