If you know that you are very likely going to launch and have a way to communicate the pitch - open up for a beta signup. Launch as soon as user can experience

If you know that you are very likely going to launch and have a way to communicate the pitch - open up for a beta signup. Launch as soon as user can experience the pitch message. The time between these two is unknown and I guess would make sense not to set a concrete launch date. The sooner the user gets hands on it the better.