About plans, as you may read in blog post (link from @Mehtaz above) we already started upgrade our templates to make them J4 compability.
Helix3 for J4 should be also ready in September.
Also our extensions are successively improved to improve their compatibility with the new version of Joomla.
I am pretty sure than till end of the year (Dec) most of our products should be Joomla 4.x ready.
For example: Raw Helix Ultimate 2.0.5 + SP Page Builder Pro can be used in both J3 and J4.
Serverl days ago we alos published first J4 ready template.