Oofā¦ Thatās a tough one. I donāt think thatās actually possible, but what IS possible is to simulate it. The first question is: do you know where your breakpoint is in terms of page width? If so, weāll call that x (940px?) and go from there.
Make another group (group c) and put it below the group a and b line. Make it invisible on page load and add a condition to make it visible only when page width < x.
Go to your responsive editor, and add a hiding rule to group A on your breakpoint.
Put the exact same content (reusable group?) in groups A and C. Should do the trick.