Having looked at it, I worked it out. The cable was loose so I tightened the adjusting nut three turns then secured the lock nut again. The clutch engages now when the pedal is about 40cm from the firewall. All back to normal, engaging first and reverse and normal gear changes easier.
This had worsened slowly and I should have looked at it before, but until yesterday I could engage first. It just slipped over the line from difficult to not available.
Thanks for the help.
