Messages (SMS) Composed on W10 Don't? Sync Back To WP8

[EJDJr]

Trying to figure out if this is a bug, known or unknown or an actual limitation.
I recently started using W10M on my daily driver (1520 - I've been using it on my 640 and 635 without SIMs so I never tried texting). After rolling my 1520 back to 8.1, I realized all the SMS messages I composed didn't sync back to with 8.1 (have not synced back to my 520 on 8.1). The 635 and 640 with W10M did get the messages synced. Also the W10M texts aren't syncing (or visible) with Outlook like all my 8.1 texts.
This is all with the current 10586 build. Anybody know or experience this too?

 

[beachedwhale42]

I was on 10581 for a week and a half, then 10586 for a day on my 920 before reverting back to the abundance of battery life we call 8.1. None of the texts I sent during my time on W10M showed up after I reverted.

 

[Paul Hellman]

Don't know if it's related, but I just got the 950 and I don't get an alert or my messaging tile does not show a missed message, yet when I open it I have missed messages. Maybe it's a WM10 bug?

 

[msirapian]

My theory :

1. MS have changed the SMS back up system with build 10572. Every message sent or received when on >=10572 is saved with the new standard,
2. Your previous messages will be converted to the new standard when, for instance, you upgrade your 8.1 device to 10586. Then all messages are in the new standard. I have 2 devices on W10M, and because of this (especially because I had one on 10549 and another on 10572 then 10581), this conversion process has created duplicates or triplicates.

So don't worry. When you upgrade your 8.1 device to 10, the "new" messages, apparently lost, will be restored.

2 things I have noted :
1. The new standard messages are no longer visible in outlook.com
2. The new standard backup process restores by thread. All messages from contact X, then Y, etc. Before 10572 (and on 8.1), it came back chronologically.