Going on 3 weeks now and I'm still missing the 9 night from my last stay 4-13th August.
Before the 18th there were showing in my SPG account, from 18th the 9 nights are missing.

How hard is it for them to get it correct from the start..... SPG showed 24 nights, then they did there IT magic and 9 nights gone.
So if I combined accounts I should have 24 SPG + 1 Marriott making me Gold Elite but currently would only get 15+1= 16 nights keeping me at Silver.
If I checked in today/ tomorrow etc. without it corrected I am not getting status recognised correctly.
Luckily I don't have any more bookings in the short term.

The fact that they haven't corrected this really obvious issue more than two weeks later, when they obviously have the necessary data, is frankly scary. This whole thing is spiraling down the toilet.

Nights still incorrect for me too. If they cannot fix it, perhaps they could staff the lines with people who will liaise with customers and go through the tally together and manually set the stays/nights? Sad it comes to this, but they should bring this to an end.

Agreed. There are unforseen issues with deployment sequences causing outages or delays, minor missed dependencies relatively unimportant and untested secondary systems have with the core platforms being migrated, and sometimes even issues with data migration (although data migration is one of the easier things to test...) - but those are issues that are either (a) not very important or (b) able to be fixed very quickly whenever the minor issue is ID'd.

To say that whatever this issue is was "more complex than anticipated" just strikes me as poor business requirements management and quality assurance and general program management incompetence. This is literally one of the most important customer facing elements of the loyalty program migration and.. the fact that people's nights were going to be totally wrong was just completely missed?

This sort of stuff was more excusable back 15-20 years ago before the day of hyper high performance in-memory, SSD, and distributed file store based databases (e.g., Hadoop) - going in and re-calculating against billions/trillions of rows of data was an engineering effort in and of itself. These days? Those types of queries can be run in seconds - and the update to the prod databases wouldn't take much longer even if it necessitated a short outage.

Today my SPG account is now accurate, as far as night totals go. YTD and Lifetime nights are correct. Neither were, as of yesterday. 2 missing nights from early August have been added.

Now, just missing line items for a nine night stay after August 18 to see if the points added are correct.

It's looking good to me.

Today all looks correct on my account.
Now to merge or not and see if any other issue pops up..........

Merged went ok, only issue is the app on phone does not reflect correctly against logging onto the website on my pc and also the phone app thinking I only need 1 more night to make Platinum Elite when it is 25.

Same here. YTD and Lifetime nights are now correct. Some of the other data in the Account Activity from before August 18 is not correct but it doesn't matter because clearly there's no link between the historical data and the YTD and Lifetime nights. I suspect they implemented a "Year Zero" on August 18 with absolute values copied over (incorrectly).

Let's see if this is a new dawn.

Plus one! All correct in mine, too.

My night count is better, but not correct (-2). I suspect a stay started before NYE and ending early this year.

If the stay started in 2017, only the nights 1 Jan or later for that stay will count. Since it is a nights based program, there is no guess work needed for when the stay posts as the nights would be credited to the year in which they occurred--not when they posted.

+1, everything seems to be in a good shape now

the app updated tonight and my YTD nights are now correct.

Update: line items for my stay after August 18 appear now, too. I'll do the math when I get back to my hotel (Novotel ;) ).

Glad I was patient and didn't let the stress on here bother me.

Now for a stressful billing error to deal with......