Catfood Earth 4.20 is available to download.
This update includes the 2021d time zone database.
After procrastinating for far too long I have also migrated to .net 4.8 and renewed my code signing certificate. You'll get at least one less warning when installing and you no longer need to enable .net 3.5 on Windows 10 which was a pain. This shouldn't make any difference but please let me know if you have any trouble installing or running this version.