If I understood correctly, in your presentation you said that, two hours after sending said letter, you heard the NDP leader asking a question in the House of Commons regarding the letter you had just sent. Question period is not scheduled for 11 p.m.; it is from 2:15 p.m. to 3 p.m. That means that you sent your letter during office hours.
On March 21st, 2011. See this statement in context.