I was never really a fan, they just seemed to be around all my life until my mid 20 s.
I watched a documentary about them some 10 years ago, or so. Lancaster had emigrated to Australia and used to just meet up with the others to record and tour. He flew in for the Live Aid concert, played the set and flew back to Oz. Rossi and Parfitt kicked him out, no reason was given.
The doc I saw was them meeting up after 25 years. He died from complications from M S, which is sad.