You are right: travel medical insurance cannot be purchased more than 6 months before the departure date, but Trip Cancellation & Interruption insurance must be purchased within 15 days from the first non-refundable deposit. In some cases, that first deposit could be given many months before the departure (sometimes more than a year before!) If this happens, it will not be possible to purchase your protections online. To ensure you get all of the discounts you are entitled to, speak with your representative, who can make an exception in such case.