There’s no proper built-in way of doing this. When this has come up in the past one workaround that’s worked for people is to just create a simple object on its own layer with cut settings set to 0% power where the duration of that cut is sufficient to start air.
Alternatively, for a Line operation I suppose you could set a “Start pause time” at 0% power in Advanced tab but probably not ideal to do this in your proper layer settings as it may cause confusion.
The addition of sublayers could potentially be used in a similar way.