Are XBOX services discontinued across devices (PCs, tablets, and phones) running Windows 8.1?

Good day,

I noticed for several months now that things have changed as it pertained to the XBOX Games app and its services on Windows 8.1, Windows RT and Windows Phone 8.1. I own a Surface RT, a Lumia 928 and a few Windows 10 PCs. The tablet and the phone are stuck
on Windows 8.1 and cannot be upgraded.

First, the Windows 8.1/RT version of the XBOX Games app (on Windows 8.1 and Windows RT) does not sign in to XBOX at all. The app shows an endless signing in loop instead. However, the same app on the phone (running Windows Phone 8.1) signs into XBOX up until
now.

Second, XBOX achievements earned on PC/RT Games are registered on the XBOX Games app on the phone. However, XBOX achievements earned in apps on the phone are no longer registered and this ended some time in March. Likewise, when viewing the list of games
you played on Windows 8.1 that carry XBOX achievements, you do not see the changes reflected. Only when you select an individual game, you see the changes. Only the Game Points that pertain to the Windows 8.1 achievements are recorded on the XBOX Console Companion
app (Windows 10). The corresponding achievements, however, are only recorded on the Windows 10 XBOX app if the games themselves were not rebuilt from scratch to work exclusively with Windows 10 (Examples: Despicable Me: Minion Rush which still works and UNO
with Friends which is now discontinued).

Finally, I noticed yesterday that Microsoft Solitaire Collection that runs on Windows Phone 8.1 did not connect to the XBOX server. Thus, it is difficult to see the achievements. Likewise, cloud progress cannot be accessed so games started on phone cannot be
completed on the tablet and vice versa. But the app for Windows 8.1 and Windows RT works quite well (in spite of the fact that the updates are exclusive to Windows 10). Wordament on the phone still connects with XBOX and achievements can still be earned there.

My question to Microsoft is if the XBOX services will be completely phased out for Windows 8.1 devices. If that is the case, I am requesting that some kind of announcement be made on the website so that we who still own old devices and better know what to
do. People have been complaining that their achievements on Windows 8.1 and Windows Phone 8.1 (in particular) have not been registering on the XBOX Games for Windows Phone. I am also requesting that if the service will be phased out, it is phased out in a
uniformed manner. If all of this is not the case, I am requesting for this to be looked into as some of us would like to complete our achievements before it is really too late. Please look into this. I can send screenshots if you like. Thank you.

:)