Thanks SSD, I too was airborne in G-OPET just around the time this occurred, flying over to Crosland Moor. I think I may have seen you departing Barton as I was preflighting.
What a perfect day, prob. the best this winter up our end of the country, such a shame it was marred by this tragedy.
Happy to go up in 'SL once you're happy with it.