You only have to read the weasel words.
"The major barrier to resuming flight has been understanding tolerance levels of aircraft to ash," the CAA said. "Manufacturers have now agreed increased tolerance levels in low ash density areas."
Lord Adonis said safety was the "paramount concern" but research into the effects of the volcanic ash had led to a "better" understanding of the implications.
The whole debacle is what I expect in this, " Oh god. I'll be sued" mentality that has a hold on the UK today.