@anon45965781 update me with the following:
Steve Kuresh wrote me back and, as I feared from reading the license agreement, FDS 19 no longer offers concurrent connections like it used to.
So for those who consider purchasing the FileMaker Developer subscription to add testing capabilities to their FileMaker development platform, please note that testing anonymous concurrent connections isn’t an authorized use case. You may however reattribute user licenses to new testers once the first ones are finished with their tests