Hunting and Airwork, on their cheap-fare equivalent service, termed the Safari Service, also stopped at Wadi Halfa. Here's their 1959 timetable. Weekly to Salisbury and twice-weekly to Nairobi. The two operators merged at the end of the year to form British United.
http://www.timetableimages.com/ttima...c59/hc59-1.jpg
http://www.timetableimages.com/ttima...c59/hc59-2.jpg
Ethiopian Airlines were also making fuel stops with their Convair 340s on their Addis Ababa to Athens runs in 1956.
http://www.timetableimages.com/ttima...t56/et56-2.jpg
Someone's also put a photo (halfway down the page) on Facebook of a Trek Airways Viking at Wadi Halfa in 1955 which (if the caption is accurate) shows a remarkably paved and mainstream runway in the background
https://www.facebook.com/TrekAirways?v=app_2373072738
The Central African Viscounts were remarkably long-lived, of the basic five delivered new in 1956 (VP-YNA to YNE) the last (Z-YNB, the original VP-YNB) was withdrawn from Air Zimbabwe service in 1990, after 34 years use from the same base, most of them having been with Air Rhodesia along the way after CAA broke up. Obviously they weren't doing runs to London at the end ! One, YND, was the aircraft shot down by terrorists at Kariba in 1979, while YNE was the one lost at Benghazi in 1958. The fleet had been later topped up with odd secondhand examples.