My computer has been away for repair hence I've not responded before.
I've had my car to Subaru dealer. It turned out that the dPf was so clogged up the management system just turned on the various lights. The level of clogging was the highest the mechanic had ever seen, the regeneration should kick in at 40%, when mine reached 79% the management system gave up trying to regenerate the DPF. A forced regeneration was carried out and managed to recover the DPF otherwise it was over £25000 to replace. The car is going better now than when I bought it and I suspect there was a hidden fault when I bought it. I've only ever had a flashing DPF warning, never a solid illumination which is supposed to come first.