Now, now PP that was rather rude, bearing in mind that you asked the question, and others just tried to answer as best they could.
The answer is quite simple. The website is not up to date. They had 57 Q400's some months ago, but several newer (owned) aircraft were sold to South Africa. More recently the oldest Q400's have been leaving, one at a time, as their 10 year leases expire. The CAA listing includes G-JEDK which is the next to leave, is no longer active, but is still on the register. Airliners show this one a 'stored' - hence the difference 48 or 49. Simples!!
