It's the discussion thread at the top of this Windows 10 forum, at the link below:
https://www.cnet.com/forums/discussions/windows-10-october-2018-update-released-today/
And as mentioned in those posts, I've now installed Version 1809 on three different computers and I've had no problems with losing files or anything else in particular, except for a few settings which were changed back to default.
On the other hand, one individual in the discussion did lose files. I'm thinking it may have something to do with OneDrive settings and/or possible Microsoft logins. On all the computers I've tested so far, they are all local logins with OneDrive disabled. All files are saved to "My Documents" and none were lost. Just guessing though.
Hope this helps.
Grif
You may want to hold off on Windows 10 October 2018 (1809) Update as people have been reporting that their files are being deleted. No word yet from Microsoft about this. If you are going to go through with the update, make sure you back up your important files. Here are some resources of what is being reported and how to stop the updates for the time being:
ZDNet: Windows 10 October update delete your files? This tool might recover them
ZDNet: Windows 10 October update problems: Wiped docs, plus Intel driver warning
CNET: Windows 10 October 2018 Update may have a big problem -- here's how to delay it until we learn more
CNET: Windows 10 October 2018 update may delete your files during upgrades
Reddit: Windows 1809 update wiped my documents
Microsoft Community forums Windows 10 Pro Update version 1809 (10-2-18
MSPowerusers: Some users are complaining the Windows 10 October 2018 update is deleting their files
If any of you updated to 1809 and the deletion occurred or it didn't happen to you, please post it here, so we can get a sense of what people are experiencing. I hope this isn't widespread or it's going to be a disaster.

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