Only just found this thread.
2 months ago 643VGS at RAF Syerston was closed.
Due to conservation of airframe hours 644VGS, also at Syerston, converted from Vigilants to Vikings about a year ago. Now this year the powers that be decided to merge the 2 squadrons into one and chose to keep it as 644VGS (even though 644 is both the junior squadron and had not been at Syerston as long)