Hi Carlos, Thank you, yes the plugin is working fine in all Unity versions I tested, and we are using 2018.4 at the moment, which is new enough Thanks, Matt
I was interested as well in the answer to the original question. When I activated a new personal license, it shows 'Team License' in the 'About Unity' section, which (I think) is what Unity is calling the 'Legacy Team License'. And therefore the Plastic SCM Unity plugin works fine. So the answer is: yes, but every version of Unity now includes that team license.