Contrary to other airlines, Ryanair does not specify this. We recommend that you check-in baggage as early as possible is what they have to say about this.
But here comes the big one: The Bag Drop desks open two hours prior to the scheduled flight departure time. At CIA, that is obviously not the case if the airport only opens at 4:30 and the flight departs at 6:15. They aren't adhering to their own published policies which any customer can reasonably expect to be in place at any airport for any flight.
If they tried to make someone buy a new flight at walk-up prices after one missed their original departure because of Ryanair opening check-in too late - well, IŽd say you'd have no problem at all to prove this in court and get that money back
See https://help.ryanair.com/hc/en-us/ar...ort-Timeframes