What's the timing of ongoing effects expiring?
All "this turn" effects wear off at the same time. For now, assume
all normal Time Passes activity
(discard, lose elements, clear damage, ongoing effects expire) is simultaneous. Cards like "Gift of Constancy" (which modify discarding Powers) or "Unquenchable Flames" work because they explicitly specify a timing.
Rules for non-standard things that happen during Time Passes (like Shroud of Silent Mist's "Slow and Silent Death") can be done before or after effects wearing off unless otherwise specified.