Using Classic Outlook on Windows for personal email, calendar, and contact management
Er, whatever problem I thought I was encountering, appears to have been fixed or was an illusion.
I swear that when I added folders typified by the x suffix, under 2024, in new Outlook, they did not sort rationally, they now do.
My apologies to Microsoft if I was deranged, and my congratulations and gratitude if I wasn't!
AH! Hang on. What happens if I change a folder? Still good!
On this basis I'm moving to new Outlook.
Regards,
Martin