We can reveal a new clash between Ryanair and consumer protection organisations.
We have a Ryanair internal memo which instructs the airline's call centre staff to offer alternative flights on other airlines - so long as the cost "does not exceed 3 times the value of the original Ryanair fare".
It has further enraged the airline's critics, who say there should be no such limit.
Alex Neill, managing director of Which?, said: "Ryanair appears to be plucking figures out of thin air as there is no legal basis for the arbitrary figure they've set.
"The law says passengers must be rerouted and there's no specified limit on cost.
"This yet again highlights the importance of the action which the Civil Aviation Authority has started. It must force Ryanair to immediately change its behaviour and comply with the law."
We also revealed the contents of the memo to the Civil Aviation Authority and asked if they thought it was legal - their reply was simple.
"No, we do not regard this as legal. We have just written again to Ryanair", their spokesperson said.
Ryanair told us they believe their interpretation of the law is both legal and reasonable, and made the following statement: