I think everything is a backup with the possible exception of the landing pads. You may need to land the Starship before the booster has been cleared from the

I think everything is a backup with the possible exception of the landing pads. You may need to land the Starship before the booster has been cleared from the other landing pad. In fact, the second landing pad is one of the new items in this iteration. Basically, I think they want to keep up the testing cadence without having to delay things due to maintenance. They say in one of the applications that there will be no more than about 10-12 orbital launches from Boca Chica per year.