Yesterday G-SAJG - Loganair's newly named "Spirit of Teesside" - stopped off on the way form Glasgow to Norwich. The plane was at the airport for about 90 minutes during which the mayor apparently did a photo shoot.
Doubt they would be going to all this effort to promote already announced routes so maybe we will soon hear something about Loganair starting LHR? Heathrow website now showing the first flights on 8 March for LM551/552 & LM559/560 (but take that with a huge pinch of salt).