cozumel beach break excursion

[fozzy]

We have booked the Cozumel Beach Break and it says that includes taxi ride to and from pier. The exucrsion allows 4 hours at beach. Does anyone know if you can stay longer than excursion allows and still get the taxi ride back that goes with the excursion? or would you be on your own to get back and pay for taxi yourself? Ship is suppose to be in Cozumel until midnight and we thought we would like stay at beach longer. thanks fozzy