F1 CPT to H4 COS + EAD

My wife is currently on F1 CPT and I need some information reg H4 COS + EAD.

  1. My understanding is that the H4 COS and H4 EAD applications can be submitted concurrently. Does the effective date of H4 start when the EAD is also approved? Or, even in concurrent filing they change the status to H4 first and then process the EAD application? Can she continue working on CPT until the EAD/confirmation is received?

  2. What is an approximate timeframe for H4 COS + EAD right now?

  3. Next year we’ll have to travel to Canada with COPR to receive the PRs. Can I (H1/ i140) and my wife (h4 ead by that time, hopefully) get our stamping done in Canada? Is there any downside to get the stamping done in Canada?

Thanks for suggestions in this matter.