I know the first OP mean when will be posted at UK download pages but there is also at the main FTP of Taiwan
ftp://ftp.draytek.com/Vigor2820/Firmware/v3.3.7.4/Annex%20A/
About the broke feature, there is a note how to update it with out possible issues
ftp://ftp.draytek.com/Vigor2820/Firmware/v3.3.7.4/Vigor2820_V3.3.7.4_release_note.pdf
For the users who still use Firmware Version 3.3.5 (and before):
Because the functions and WUI on Firmware Version 3.3.5 (and before) are different with Firmware
Version 3.3.7.2 and later, we strongly suggest you to download the file (V3.3.5.2) from the
following FTP first.
ftp://ftp.draytek.com/Vigor2820/Firmware/
Upgrade your router with Version 3.3.5.2 first, and last, upgrade the router with Version 3.3.7.2.
... i am adding ... or later fimrwares than 3.3.7.2
