I have a plan I would like to run past some travelers to ensure it is possible. I will be staying in Merida and would like to visit Chichen Itza then head to Cancun in the same day (it will be on a Tuesday).
9am-10.30am: Private shuttle from Merida to CI (USD45).
12.30pm: Bus from CI to Valladolid (I read I should be able to join a bus from Chichen Itza without pre-booking).
3pm: First class bus from Valladolid to Cancun (hopefully arriving in Cancun around 6pm).
Any advice is greatly appreciated, I am flexible with travel times, I would like to arrive at CI earlier if possible. The only thing I was planning on pre-booking is the private shuttle from Merida but let me know if I should pre-book anything else.