I have created a number of commands for various procedures and finding that every time I make a change to my procedure, the command pointing to it either a) no longer works or it does not pick up the latest changes made in the procedure itself. Haven't tested it yet with MP, but single player world and "Run client" behave similarly.
For example, I have a command to provide a book of "actionable" commands and as I've been testing and fixing spacing, typos, etc., I save the procedure and can see that Gradle starts and compiles it. However, there is a disconnect or "cache?" that the command is no longer getting compiled "after" the procedure so it becomes non-functional. Took me a while to figure out what was going wrong as there are no errors in the server logs or compilation of the code. Once I started saving the procedure, waiting for gradle to finish and then open/save the command, it started working. I just noticed 2020.3 is released, so I'll migrate the mod to the latest version and see if it was fixed or not.