YES! this was a huge problem, I had one travel agent have our guests from halifax there SIX DAYS before we got there from Toronto!!! ummmm not going to work... we are trying to organize a wedding! I found tripcentral.ca to be a GREAT resource. If you go into their "vacation packages" tab you can list all the trips for a specific week month etc. What I did was go into these for every departure city we have, see what day was common between all the cities (or as many as possible) and than tell my travel agent the date we wanted to depart from all cities. Also, Air Canada Vacations (who we are booking with) has all of the departure cities you mentioned and what they are doing (for us at least) is everyone is connected to Toronto and then we are all on the same flight together to Punta Cana! Hope this helps, let me know if you have any other questions!!!