I know that you can still update manually but I think it is strange that my main PC hasn't received the update yet while my laptop has.
You might not have been offered the upgrade, because of the software/hardware you have. Like AMD causing black screen during boot.You better wait
The company recommends users to wait for the Fall Creators Update to be offered via Windows Update, though there’s no estimate as to how much this wait could last as it all depends on the number of bugs and issues that the company finds in the new OS version.
They will be forced to upgrade within 18-20 months of the Anniversary's release date (April 2018), regardless of compatibility problems, security comes first then.I know people who still haven't got Anniversary Update.
What does FCU stand for?That is only for Windows 10 Enterprise and I doubt OP is running that. The FCU has rolled out but it can take longer for others to receive it due to how the updating system works now.