It was self Undercoating, and still says it is on the tin. But it’s changed recently without to my knowledge any notification to us proffesionals. Whereas you used to be able to rely on it adhering to old paint, (hence the self Undercoating claim) now it sticks to bugger all without alot of preparation. Bizarrely the new Dulux quick dry range is pretty good. Anyhow, try a small area with your water based stuff and give it a good scratch test when dry, you may well find that very little prep is required as the satinwood is still fairly fresh. Dulux have always been hit and miss, with periods of their paints being good
..and not so good. The emulsion however is pretty consistent.