In trying to reply, by both methods, to a post in the "Cornwall" thread tonight, I encountered the following rejection :
" The website is unable to display the webpage
HTTP 501/HTTP 505
What you can try:
Go back to the previous page.
This error (HTTP 501 Not Implemented or HTTP 505 Version Not Supported) means that the website you are visiting doesn't currently have the ability to display the webpage, or support the HTTP version used to request the page.
For more information about HTTP errors, see Help. "
The reply was ultimately successful, but only by using two certain words in full, instead of abbreviation - ' C / L s ' [but without the intermediate spaces (abbrev'n. was to represent colour-lights') ].
I presume the problem bit represents some sort of web page or protocol, etc., code, hence the rejection?