Ryanair System Error

beverleyd_3

I booked return flights in September to Brindisi for November. I went online 1st October 11.18am under Manage Your Trip to find the webpage showed "Disruption on your trip / cancellation of flights, offering either a refund or a change of flights". I took a screenshot of the webpage to show my husband. He went online on his computer and saw there were no flights available for Brindisi for the whole of November! As we had already booked accommodation I went on an alternative carrier and straightaway booked flights for the same destination for the same dates.
Having the screenshot as evidence and taking the webpage at face value I was horrified when I went back on Ryanair Manage My Trip to find no evidence of any disruption or cancellation.
I immediately contacted Ryanair through their live chat, then contact form and attached the screenshot as evidence. After more contact and one support agent telling me there had been a "system error on this app" on the webpage I received an email with attached standard letter saying "Ryanair tickets are non-refundable". They completely ignored my screenshot evidence.
I contacted Aviation ADR 27th November and included all the details and timelime of my complaint and refund request. I received a response within 3 days telling me it was outside their jurisdiction and they cannot deal with my complaint. Is this because Ryanair have withdrawn from ADR, or is it because my complaint was not viewed as a cancellation? I don't know where my complaint sits..... I took the cancellation at face value.
Where should I go next , UK Small Claims Court, EU Small Claims Court? Any ideas would be great.