Complex sentence: Reforming in early 1967, No.11 Squadron spent the next 21 years flying Lightnings, until May 1988, by that time one of the last two squadrons equipped with this aircraft and was based at RAF Binbrook in Lincolnshire.
Split into simpler sentences: Reforming in early 1967, No.11 Squadron spent the next 21 years flying Lightnings, until May 1988. By that time it was one of the last two squadrons equipped with this aircraft and was based at RAF Binbrook in Lincolnshire.