In message , John
Rumm writes
It may be because the online process is not fully online. You can
register and complete a return online, however the supplying of the
access code and pin etc are done by post. If you already have access
details for the site then no doubt one could gain access from abroad
via VPN or proxy if direct access is blocked.

But perhaps taxcalc doesn't speak to HMRC directly at all. Perhaps
it just collates all the necessary information using a "friendly"
interactive interface, and then simply prints out an HMRC-compatible
paper form with all the fields filled in, ready to be signed and posted.

Don't laugh, but in the first few years of online filing, that is
exactly what the HMRC web site did! They re-keyed everything you
entered into their old system for the actual calculations to be repeated.


They then went to a system which was always closed for maintenance for
the week when returns were due [1]

Then a system that wasn't but crashed all the time

They finally seem to have got their act together a bit more now


[1] - referring to EOY online submissions here

--
geoff