Problem using vi in freebsd-update from 13.2 to 14.0

Hi,

When doing the merges presented by freebsd-update I have somehow got into 'ex input mode' and hitting <Escape> repeatedly does not get me back to command mode.

I had already done a couple of merges apparently successfully (including the <:a> command and <escape>), /etc/group and /etc/master.passwd, and am merging /etc/ntpd.conf.

I do not use the vi editor often, and have a session showing 'man vi' which I look at before doing every command.

My route to where I am is:

ssh <box to be upgraded>  # from an OpenBSD box if that matters.
su
freebsd-update -r 14.0-RELEASE upgrade
# watch things happen till prompted to do manual merges.

Then in the vi (?) session type
:a

to which the response is:
Entering ex input mode

I found the page 'jakeworth.com/exit-vim-ex-mode/' which does not give me a get-out but does suggest entering 'ex input mode' by accident is possible.

So, how do I get out of 'ex input mode' in my case?

Or can I just kill the session running freebsd-update and restart freebsd-update assuming it will pick from where it had got to?

Roger