New solar-powered "wait" buttons with unknown purpose at TCAT stops?

I strolled by a 10 bus stop today and saw a brand new seemingly solar powered button that looks a lot like a crosswalk pedestrian button... but there's no crosswalk. When you push it, it beeps and there's a little lit sign that says "wait." Does anyone know what this is? Is TCAT starting some new afterhours bus that is triggered by this button? I tried to find info online, but could only find the news about the new microtransit offering that began today (which is wonderful. looking forward to trying it myself because the ubers are ridiculously priced here)