Sorry for coming to this thread a year late!
I have just painted my room with an old supply of Dulux Gentle Lavender and found it to be exactly the colour I have been looking for. Unfortunately, two coats didn’t quite cut it, so I went on the hunt only to find it has indeed been withdrawn from the shelves as a ready mixed paint.
Seeing that it was available as a mixer, I rang Dulux to ask if it was likely to be a different shade. The answer was no, not really. This was far from the truth! I paid £40.95 for a 2.5 litre tin from the Dulux Decorator Centre, only to find it to be a completely different colour. My walls are now covered in a horrible shade of deep, overhanging purple. I have contacted Dulux for a refund. Beware!