I'm not expecting the tracker to change until BW19, it seems to skip the 'build in progress' stage and just go straight to the shipping stage. From looking around on here, most take about a week after the BW to change on the tracker.
As for delivery.... I'm still praying it will be here and PDI'd before the 23rd May, if not it'll be sat at the dealers for a month - My company will only allow it to be released on certain dates :-( (see previous post)