The phrase "marked departure" means a noticeable and significant change or difference compared to the usual or expected way of doing something. Full definition
For Snap in particular, the move marks a departure from other tech companies — which have, in recent years, chosen low cost countries for their global operations. (inc.com)
The exhibition presents a new series of large - scale «collage sculptures» that mark a departure within the artist's practice. (davidzwirner.com)
The artist's paintings from this period mark a departure from his earlier romantic works. (en.wikipedia.org)