These became available recently for 4.0:
qubes-template-whonix-ws-16-4.0.6-202109061137
qubes-template-whonix-gw-16-4.0.6-202109061137
One issue so far: sys-whonix based on whonix-gw-16 doesn’t work as an updatevm for sudo qubes-dom0-update
:
Curl error (6): Couldn't resolve host name [...] [Could not resolve host: mirrors.fedoraproject.org]