Will be arriving at GUA on an Aeromexico flight from MEX around 10:30 PM. If I can get past customs by 11 PM, would there be shared shuttles to Antigua available?

This is on an RJ with ~80 seats. There is a Copa flight that arrives around 30 minutes after the AM from PTY, also RJ, which is the last flight of the night. Before the AM there is a Copa 737 from SJO around 30 minutes before.