Hey,
Contiki is an amazing company. I went on two contikis and I am going on another two. I would reccomend going with them.
When I first signed up my departure was not definate. I was worried about them canceling it. Then I realized why would they have these dates and be successful year after year if they are always going to cancel dates? So, I calmed down and waited.. .. .
I went on my trip and everything was fine. I had the most amazing time. I would def. go on a Contiki!!
If you are worried about the definate depatures then you can browse through ones that are def's so that you know for a fact there won't be a problem.
However, if you fall in love with one that isn't a def. don't worry, it rarely gets canceled.
-Monica-