Ryanair operates to whatever they make up on the day. Ostensibly the IAA oversees it, however the IAA doesn't exactly have a reputation as an organisation capable of overseeing anything. Remember that FR is far and away the IAAs biggest customer, and given that Irish airlines FTL's are approved on an individual basis, and not according to a standard set of rules, you can work out how the system works.
For example, FR pilots can operate up to 100 hours per month, unlike CAP371's 90 hours.