The blocking filter was sent off to Baader last week - I asked them to conduct a full service as I was concerned that any moisture / gunk / mildrew that may have gathered on the underside of the blur filter could also have lodged itself on the Ha filter on the other side of the blocking filter.... so I hope to get it back in a while looking good and giving us the sorts of views we were expecting to see, but haven't seen in over 12 months.