If you mean the Halloween internet-only thing tonight at 10.00 p.m., it's not live. It will be as-live (or so they say), having been recorded some time earlier, and repeated on Really TV, doubtless edited to some extent, on Thursday.
Really TV have indeed done Live Most Haunted in the past (at 30 East Drive.) The subsequent somewhat edited repeat blanked out "demonologist" Fred Batt reciting what could only have been bits of a Black Mass. Bet they got some complaints about that, lol.