When a designer is asked to create a pattern for a new fabric line for a manufacturer, the company usually has rights to it for a limited period of time. During that period it is often posted for free on their website to promote the fabric line. After the specified time has elapsed, the designer regains full rights and sells the pattern as usual. Sometimes, as in this case, there is an overlap.
Most fabric manufacturers have free patterns on their sites, as do some fabric retailers (notably Hancock's of Paducah), and all are worth checking out from time to time because they do change.