Unfortunately Ryanair are correct. Their Conditions of Carriage only allow you to cancel where there is a change of at least 5 hours to the scheduled departure time. There is nothing within EC261 that would help you get to your destination at or about the original scheduled time.

Depending on the date you booked, you may be able to change the date of travel under their COVID-19 policy, but you will need to pay any difference in fare.