The previous Experimental version has been merged into the current Development version. So if you have used the Experimental Version previously, you’ll get the same thing in the current development version plus a few new things included.
The current experimental version is even more experimental and used to trying out very new and emerging system that’s not really ready for public use. You can use it, but use it at your own risk and there won’t be any support given in the Discord for the current experimental version. (I don’t think the current experimental version has been updated yet)