I want to know the answer to the following question:
When did John leave for Poitou?
All the background I'm provided with is that "John was optimistic, as he had successfully built up alliances with the Emperor Otto, Renaud of Boulogne and Count Ferdinand of Flanders; he was enjoying papal favour; and he had successfully built up substantial funds to pay for the deployment of his experienced army.". Is that enough to answer the question?