Answering my own question–I was successfully Moved to Mint on a Navan-booked LAX>JFK flight ~32 hours out. My company does have a corporate discount with B6 (according to Navan, at least), so looks like corporate bookings qualify at least for now.

DId we ever get an answer on whether 3rd party tickets (Expedia,Cap1travel,Chaseportal) can get move to mint?

Cancelling after Move to Mint applied
 

If a ticket is cancelled after a Move to Mint has been applied does the Move to Mint award get returned to the account?

When I chatted with support about my corporate booking, they stated that tickets booked through OTAs like Expedia did not qualify.

The Mosaic line confirmed that Blue Basic fares are eligible for Move to Mint this year (the terms are pretty clear they aren't eligible next year). Has anyone else confirmed this with the Mosaic line or in practice?

I'm trying how to figure out how to best book a transatlantic round-trip for me (Mosaic 4) and my wife (Mosaic 3). I think the best way is to book each of us on separate reservations, so we each would use 4 certs (even though I have 6 total)? If I book us in one reservation, will that make any difference? I looked into two separate one-way reservations for both of us, but the cost is more than round-trip.

It will be returned to your account, but not instantly, at least not for me.

how many certs can i use at a time? I have 4, so can i use all 4 in the same flights if we have 4 passengers traveling?

it’s you plus 1 pax.

Confirming with actual DP that my JFK-LAX award flight was upgraded using MTM, surprisingly at around 48 hours in advance.

Works with Basic through year end. Then Blue required.

WIll these work on a fare such as ATL-JFK-LHR for the second leg? Does it matter that I'm applying the voucher to an itinerary that includes a non-mint flight?

New to Blue. Few questions on Move to Mint process:
1) If only Mint Studio left, do they give this as move to mint?
2) Do they Move to Mint if only one or two Mint regular seat available, or hold to sell?
3) At what point prior to flight do they end the Move to Mint upgrade process?
4) Seems priority is M4 before M3. Any other known prioritization?

Thank you!

Just bumping this back up to see if anybody has insights into shoodawg's questions - I'd love to know also. Cheers.

Yes works if only one flight has Mint. For 2023 move to mint is per flight segment anyways.

Only speaking to the ability of using same day fight change (not any routing differences), I was able to do this yesterday. The agent as first seemed skeptical, saying there would have to be seats available and the upgrade process would have already needed to happen on the new flight before they would move you. At 24 hours prior, I think the latter part is usually the case, but in any case I knew there were seats open on the flight I wanted to move to. After a few minutes of checking she confirmed she could do it and I was moved to the flight retaining the upgrade.

My LAX-EWR upgrade cleared this week around 36 hours in advance for 2 people and there were only 2 seats left. So it appears they will clear upgrades up to the last available seat.