Having announced it would be cancelling around 50 flights a day over a six-period across September and October, Ryanair then said this week it would have to suspend 34 routes until March next year in an effort to bring an end to uncertainty over further cancellations.
The airline told passengers they can receive a refund or be transferred on to other flights or travel by trains, buses or auto hire.
The document, unearthed by ITV News, was criticised by consumer group Which?.
Only if these options are not available will it offer passengers, "re-accommodation on any one of our agreed disruption partner airlines".
The Civil Aviation Authority ordered it to put the information on its site by 5pm on Friday or face possible action.
According to a CAA spokesman: "As yet we have received no response to this request, not has Ryanair proposed any other meetings, whether in person or via telephone".
Several popular routes used by United Kingdom travellers were hit, such as Stansted to Edinburgh and Glasgow, Gatwick to Belfast, Newcastle to Faro, and Glasgow to Las Palmas.
He added that 99 per cent of Ryanair's customers remain unaffected by the cancellations.
CAA guidelines state that if an airline cancels a flight it must offer passengers an alternative flight under European Union law.
This week (by close of business on Sun, 1st Oct), we will have reaccommodated/refunded over 90% of the 400,000 customers who were notified of schedule changes (on flights between November 2017 and March 2018) on Wednesday 27th.
If Ryanair, headed up by CEO Michael O'Leary, does not play ball, the CAA said the result may be legal action. He then issued a clarification.
"We are furious that they are not complying with the law and they are not giving customers what they are entitled to", he said.
The carrier called upon the regulator to "now require United Kingdom airlines to comply".
The airline said it will reimburse "reasonable" out of pocket expenses incurred by customers as a result of these flight cancellations, subject to receiving an expense claim form from customers supported by original receipts.
The airline has pledged to fully cooperate with the CAA investigation. The CAA has said that it could enforce United Kingdom consumer rights under the Enterprise Act, meaning a possible fine for the airline, but Ryanair would still be able to operate in the UK.
Ryanair's operating licence is handled by the Irish Aviation Authority.
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