[expr.await] p5

Otherwise, control flow returns to the current coroutine caller or resumer ([dcl.fct.def.coroutine]) without exiting any scopes ([stmt.jump]).

However, whether a variable with automatic storage duration is active or not is totally defined in [stmt.dcl] p3, which means "without exiting any scopes" seems to expound nothing. According to [basic.stc.auto] p1, the storage duration of the parameters and variables defined in a coroutine all have automatic storage duration, hence, their lifetimes are governed by [stmt.dcl] p3. Since what [expr.await] p5 says and [stmt.dcl] p3 says that

when a function returns, Q is after its body.

the lifetime of the parameters of a coroutine has ended when the first suspension occurs (which returns to the caller or resume, that is, Q is after its body). However, it cannot interpret the lifetimes of these variables defined in the body, that is, a suspension may not end their lifetimes.

If we admit the effect of "without exiting any scopes", which in turn, cannot interpret the lifetimes of the parameters of a coroutine, since the parameter scope does not exit out. In conclusion, regardless of [stmt.dcl] p3 or "without exiting any scopes", neither of them can interpret both the lifetime of parameters of the coroutine and the variables in that coroutine.