Brink said:

Source: https://support.microsoft.com/en-us/help/4469220

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Windows 10 Mobile Specifications & Systems Requirements

I have noticed and have one bug and problem with this november culmulative update today 3 or 4 times I got SIM Error and No SIM and SIM is completely functional and active.I didn't have that problem before this CU Update Last night since I installed this CU I got twice SIM Error that's all problem I got with this Cumlumative Update Build.

Interesting, we have two 950XLs that updated late last night. On one I had to do the forced shutdown routine because the process hung and then the screen went black and stayed that way. The process then continued after the restart and completed successfully. On the other, I had to do the forced shutdown routine because the process hung at the second Windows logo screen after the process had restarted the update just after completing the download step and before the "gears rotating" step. When the device restarted I checked for updates and apparently nothing in the first attempt worked, so the entire process started again. The second update attempt worked correctly with no hickups.

I'm noticing some speed improvements, especially in the Edge browser.

DooGie said:

Could you explain what the forced shutdown procedure is please.

Hold the power and volume down buttons (on the 950XL at least). This is similar to doing a restart on a Windows 10 versus a shutdown and startup. The restart clears everything and restarts the OS; the shutdown and startup pulls prior running state data from data saved at shutdown.