Encountered this today where there were no issues before, console logs follow:
Hit:3 https://download.virtualbox.org/virtualbox/debian bionic InRelease
N: Skipping acquire of configured file 'contrib/binary-i386/Packages' as repository 'https://download.virtualbox.org/virtualbox/debian bionic InRelease' doesn't support architecture 'i386'
Is this a problem with the repository, or with my own config? The same operation had no issue as recently as 3 days ago.