That Line of Succession web page is sometimes not instantly updated...I doubt it's due to any issue of debate, the statement by the King was very explicit. As to how that reflects Andrew's present status, I don't think you need to make a separation between "Andrew MW" and "Mr. Andrew MW". They are one and the same - being the latter to which anyone even commoner has of course. The King's statement was very explicit AFAIK about removal of all titles, so all that remains is what style (?) might remain. By which I mean - as the son of a Duke, is he not at the minimum styled as "The Hon. Andrew"? Being a form of address only of course, and not any form of title..