We still have no plans to support 5.0, or later, on Python 3.8, but I am now considering the following to make it easier for those unable to use other than Windows 7 to possibly run the latest version.
Have an automated attempted build of our "stable" branch (which is almost always exactly what we release, but might be slightly ahead or behind at times) under Python 3.8 on either a daily basis, or when changes are made to that branch.
We would not support use of this version in general. Any bug reports using it without the requested log files will be absolutely ignored. If the logfiles don't make it clear that the issue pertains to a bug in our code, rather than an OS issue or similar, we will request the bug be reproduced under the latest supported build. We won't even guarantee that installations using these builds will work. If the build breaks it won't be a priority to fix it. If we make code changes that cause Python 3.8 to no longer work, then this not-really support will end.
It will take some developer time in order to set this up, so don't hold your breaths. Our policy is still to recommend all users of the EDMC Windows builds be using a Microsoft Supported OS, with Windows 7 not counting, even if you actually paid for their extended support.