The pattern for 'Garden Party' is in the lates issue of 'Popular Patchwork' and should be in the shops now. you can read more about the fabrics used in the quilt here.
I think the challenge may have been for the 2002 Wrexham Quilting Circle exhibition. Val Shields found some photos from that exhibition showing the other Split Nine Patch challenge quilts, and my 'Time and Again' quilt was included. I made Time and Again for the 'Memory Lane - a social history in cloth' challenge at the National Quilt Championships at Ascot 2001 and I am sure I sent it to the show organisers before setting up day. As the WQC exhibition falls the week before the NQC show, I am sure this must date the challenge photos to the following year. So I started the quilt in 2001 and finished it in 2012!