I have an OC9 cert in my account that I'd like to attempt to convert into NC7.
I understand it is a draw of luck getting an agent who is willing to do it for me (as OC9 maps to NC6), but assuming I get an agent who is willing to do the conversion for me, I'm a little confused how many extra points would be required in this case:

1) The difference between NC6 and NC7 is 60,000 points, according to Marriott's latest travel package website (the new travel packages).
So would I have to pay 60,000 points?

or

2) According to the wiki info on this thread, the refund value of OC9 is 165,000 points and while the refund value of OC Tier 4-5 (the one that maps to NC7) is 315,000 points.
Would I have to pay 315,000 - 165,000 = 150,000 points?

Almost certainly it will be #2 . Your OC9 definitely has a refund value of 165,000. The only person in this thread to report getting an NC7 partial package got it as a QL87 which costs 315,000 points. The package mappings we have are based on the old cert values. Even when an OC is converted to an NC the values are based off the OC value so your cost will be 150,000 to upgrade - IF you can find an agent willing to do it.

Just another datapoint.
Call 1
Talked to what appeared to be a competent agent - US line. Had an OC9 attached to a reservation that wasn't going to happen.
Mentioned OC and agent said yeap, I know how to detach and convert. It was very quick, and he changed the OC9 to NC6 in a couple of minutes and then attached to a new reservation (yesterday)
Thing was when I checked the following morning, I found out that 20k points were deducted to convert an OC9 to NC6. - never mentioned anything about point deducted - just one time new anniversary date for the new certificate.
Call 2
Talked another agent that understood the gist of what i was saying that there shouldn't have been an extra 20k points deducted, he was in the process of helping when I got disconnected and couldn't call back for an hour.
Looked online at my account and then found out I had another 415 k points in my account and a partial package travel package 6.(no code) and somehow the certificate was detached from the reservation.
Call 3
Talked to another agent, and after she re-attached the certificate, my account went into negative points. At that point she went to fix it up with the manager and everything seems fine now.
Unfortunately I dropped from platinum status to gold. (Was platinum through Ritz card - opened back in aug 2018.)

Today I called the UK and US numbers, and was told they are unable to convert my OC1-5 travel package to a NC1-5 travel package, even if I pay the difference of 60,000 points. Has anyone had recent success in doing this? Thank you.

So, I've spent around almost 3 hours today with 3 customer service representatives and still no end in sight over what I thought was a minor adjustment in my reservations with an OC9/TP 5night certificate. I booked this Category 9 certificate for 5 nights at the JW Essex NY Marriott for April 28 to May 3, 2019, prior to the merger of reward programs . Today, I had a slight change of plans and wanted to reschedule this reservation for April 24 to April 29. I specifically asked the Titanium Plat customer service rep if I could use the OC9 certificate for my modified reservation for April 24 to April 29 and was told that she would apply that certificate to my modified reservation. I then booked flights for my wife and I based on this modified reservation.

A few hours later when I checked my Marriott Rewards/Bonvoy account at a Starbucks Coffee Shop, I saw that my account now had been debited 240K points from my balance and that my OC9 5 night certificate had been restored in my account with an expiration date of May 30, 2019. I called another Marriott Titanium Plat rep again, explained the issue, and was told that my old OC9 5 night certificate, after a 25 minute hold and recheck with some others in her office, could apply to the modified reservations. (This advice was given to me after I tried to get my OC9 extended beyond May 30, 2019 or after I tried to get my original reservations back with the OC9 attached, if possible, as I had 24 hours to change airline reservations.) I was then placed on hold for anoither 15 minutes and waited for the contirmation -- with my phone battery on limited power I told the rep I couldn't stay long prior to being placed on hold. I had to hang up as power was drained completely on my phone.

I get home to look at my Bonvoy account and nothing has changed; 240K down in the account and OC9 with an expiration date of May 30, 2019. I spent an hour with another Titanium Plat, who explained she was powerless to attach the OC9 certificate to my modified reservation, that she could not convert my OC9 to NC6 with an expiration date beyond May 30, 2019, and that the best she could do was write up a case for me and send it up the chain of command to those who might be able to grant me some relief,

What a mess! Anyone have similar issues?

1. Change your 5-night reservation to a points advance one online, which should restore your 240K in points to your account.
2. Call to convert your OC9 to a NC6, which should extend your certificate to one year from the date of change.
3. Once you have a NC6 in your account, ask to have it attached to your points advance reservation.

I am intentionally using the word "should' instead of "will."

Thanks for the information. I'm going to wait until I get notification about any resolution about my case. I think the problem I have is that my OC9 mapping to a NC6 has been devalued in the process as the hotel I orginally booked with the OC9 is now a Category 7 hotel. I'm trying to get an upgrade to the NC7 in light of all these circumstances with the incorrect information initially given to me by the two reps and my booking airline flights in reliance of that information.

Good Luck on the "resolution".

Have you not read about how long it has taken for people to ever hear back or not hear back at all?

You do know that if the hotel changed category after your booking, ANY touch on the reservation, incl the date change, would VOID the payment, i.e. the old cert that is no longer good for the increased pt requirement?

What you think is a minor date change, may be just your wishful thinking, hoping to pull it off on the change while you KNOW that the category change would cause problem when you removed the cert - now you tell us and no wonder there is the drama.

With more truth has been told, no wonder you have gone thru such drama because you are trying to do the impossible which badly backfired.

What my321 suggested is the easiest solution that should work, IF there is no category changes. Now all bets are off.

Since the category has already gone up since your initial booking, you would need Marriott to really bend backward to help you restore the reservation.

I seriously cannot believe we still hear this kind of drama as of now, after we have learned what can be done and what cannot, and on how to get it done on those that are within rules and are possible.

Took about 9 calls, but finally got a rep to convert my L870 that was attached to a RC reservation into a QL87 which I attached to a category 7 SR that's going up to category 8.
Truly amazing the whoppers I heard on the first 8 calls about why it couldn't be done.

Just converted my old category 1-7/7nights certificate to a new Cat 5/7nights certificate. Very easy process. I got a supervisor on the first try who knew what he was doing. Quick process and the certificate showed up instantly in my account. It really helped that I could state that I needed a QP91. The new certificate is valid for one year from today.

Since we technically are not allowed to convert our OC to a higher category NC, it probably isn't worth not burning 60K Bonvoy on a stay just in the hopes of using it later to convert an OC5 to a NC5?

Sorry if this was already asked- i couldnt find it, but if I have ONE cat 9 legacy travel cert and i am undecided about which hotel i will stay in. can i book multiple reservations on points (NOT point advanced) and apply the certificate after the fact to the paid reservation?

the certificate is not even allowing me to apply it online now anyway, and i dont really want to spend 2 hours on the phone tonight to do it (plus im undecided between europe and asia)...

thanks for the help!
r

But that's just the *correct* conversion from old Tier 4-5 to Cat 7, as it should be. The hard part is say for an old Tier 1-3 holder to bust out of the corresponding Cat 6 and into a new Cat 7...