We’ve conducted many tests in the past that require testers to test at the same time. Examples include: multiplayer games, video chat apps, learning apps, game shows, etc. This typically requires the Managed service, since it requires refined targeting and multiple sessions.
During the screening survey before accepting testers into the test, we can ensure users are available at the required day/time. Then we can have an onboarding survey due the day before, to ensure they complete any installation / registration before the actual test.
If it’s ok if testers complete the test within hours of each other (e.g. between 12-3pm), then the Pro product usually works fine, depending on the number of testers, demographic requirements, and complexity of the test.