I read several posts about loss of cellular connectivity (and many other issues) after upgrading to IOS 14.0.1. I tried the suggested fixes (turn on Airplane Mode then turn it off; Reset Network Settings; Force Restart) but no success.
The solution that worked for me (sorry I didn't save the name of the person who reported it) was to delete my VPN app. Then I restarted my iPhone 8 Plus and cellular works exactly like it should.
KarenL
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