To me, an expatriate for tax purposes is normally someone who works or lives away from their home country.
In these circumstances you the expatriate are in a foreign country and getting to grips with a new tax regime.
“I am an expat myself and I think this helps me understand your general situation better.”
Using email for communication means time zones are less of an issue and as I tend to use .pdf format for most of my communication, tax forms and advice letters this speeds up delivery straight to your email inbox without any risk of international post delays.
This coupled with electronic filing of your main UK tax forms means turnaround is much faster than other methods.