Is the buyer or the seller 'travelling'?
Canada Post has a paid option for Holding mail while the customer is on vacation (or any reason,actually). CPO also offers mail forwarding. Both are very useful services and worth every penny.
If the seller is 'travelling', she will not be able to ship your purchase.
If the buyer is 'travelling', he may not be able to pickup up his purchase. That could lead to problems, but if the seller was notified it is likely/possible that the item was tracked.