I bought a Leicester longwool fleece at Woolfest, as nearly all the bags of dyed Gotland locks had gone from my big sack of various dyed fleeces. It was huge and grubby, but rather to my disappointment not nearly as well skirted as I'd have expected, given that it was expensive and bought by weight.
Most of it washed and dyed easily:
However, I refused to throw away the stuff I'd have skirted off if it had been a cheaper fleece. I stuffed it in the larger bucket (and it was full, that was how much fleece there was), covered it with cold water, and left it to soak for four days. It's warm at the moment - I'm sure you can imagine what fermented sheep poop and filthy fleece smelt like when I poured it out. In the kitchen.
But two very hot and soapy soaks later, a rinse, and then dyeing, in one of my large pans on the hob rather than a pan in the oven, and it came out beautifully:
It then spent three days drying outside - there was no drying space inside, with bfl/silk tops on the drying rack, and two baskets of alpaca fleece on the creel in the living room. Being dampened with a bit of rain, and a few days of hot sun and breezes made sure there's not a trace of sheepy whiffiness left on it.
So, lots more locky fleece to bag up. Of course, I've only just remembered to order more bags on eBay, I ran out of them packing stuff up just before Woolfest.