I completely understand, but unfortunately, I have to say that this is not practical.
The issue is that we are constantly adding new PHP versions because the security ecosystem itself requires us to do so. In practice, this means adding the new versions to additional slots.
However, we have encountered situations on some of our servers where the primary PHP version slot has become obsolete, preventing Roundcube from being updated.
This raises several important concerns that I believe should be addressed. For example, if I have multiple slots with different PHP versions and later change the PHP version assigned to one of those slots, that change directly affects all users who are using it.
For this reason, the PHP version selected by each user should persist independently of any subsequent changes made to the slot itself. I believe this is an important issue that the DirectAdmin developers should investigate thoroughly.