I plundered a bit this at first, but the uppermost icon is an action button, and the bottom one is a status button (which happens to provide an action menu).
So it does kind of make sense, and at the same time could be a little unclear.
Could it be made clearer? Most likely, and I’m thinking either having all three modes available at the top with the current mode greyed out, or possibly have another icon indicating the switch mode status somehow, could be an improvement.