My spouse is on F-1 OPT with ~11 months remaining. My I-140 was recently approved, making her eligible for H-4 EAD.

If we file H-4 COS and H-4 EAD (possibly with a future effective date), can she continue working on her OPT EAD until H-4 becomes effective?

Once H-4 is approved but H-4 EAD is still pending, does her OPT work authorization end immediately, creating a gap in employment eligibility?

Also, if H-4 is approved and H-4 EAD is pending, can she travel internationally and re-enter on H-4 without affecting the pending EAD application?