That would be correct.
Keep an eye on your registered email for an email containing TST login, it may also get filtered into your junk/promotions folder so it can be useful looking there too.
Please recall that the TST is only available certain hours of the day to ensure high server capacity for testing and to reduce the number of bots needed in games.
The TST server is available daily between the 3rd and 8th, 12:00 (UTC)–20:00 (UTC) (7am - 3pm CT)
Outside these windows it is taken down.