Could not upgrade from Catalina to BigSur

Sucessfully installed Catalina to my Lenovo Legion Y7000P with Open Core 0.6.4. Try to upgrade to Big Sur from Mac OS. It downloads the Big Sur installer, ask for reboot.

Once reboot, I select the Mac OS install option, it stuck at the apple logo with progress bar at 5%.

Do I need to do anything special for Big Sur update?

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Also I tried to download the Big Sur recovery image to USB EFI folder directly with python script as in the open core installation guide. But it seems that Apple removed Big Sur recovery. I got Catalina version.

https://dortania.github.io/OpenCore-Install-Guide/installer-guide/winblows-install.html#downloading-macos

# Latest version # ie. Big Sur(11) python macrecovery.py -b Mac-E43C1C25D4880AD6 -m 00000000000000000 download # Note, Apple has temporarily removed Big Sur from the Recovery Catalog # Expect Apple to resolve this sometime after the holidays 

Thanks.