ZoSo

My take is that because it's a Jubilee, an amp Slash hasn't used to record any GN'R material with in the past because it's mainly used just as his live amp, my guess is that he is re-doing bits and pieces of his work over the top of a NITL live album. It would probably just take an afternoon, or a weekend at the most, which would fit with his schedule of getting back on the road. Axl's house studio will be chock-full of NITL material that he'll be going through, thinks something needs a bit of polishing from Slash for an otherwise perfect song, and he's called him in to get it done.