Red Bee have subtitlers all over the place - for example, I know that Midlands Today in Breakfast this morning was subtitled by someone at Queen Margaret Drive in Glasgow. Overnight subtitling on News 24 is sometimes done by the Australian Caption Centre, which is now owned by Red Bee.
Also, a lot of live subtitling is now carried out by 'respeaking' - someone listens to what's being said, then talks into some text-to-speech software, also reading out punctuation, etc. It's not quite as accurate as stenography, but far easier and cheaper to train people for.
There are subtitlers who work from home. There was an article in the BBC staff magazine a few years ago about a woman who live subtitled News 24 from her house which overlooked the Firth of Forth! She did half an hour at a time and someone else in another part of teh country did the alternate half hours