Can you take loestrin 24 until the day you start depo?

There shouldn't be a problem with doing that. :) Pills are much shorter acting, which is why you have to take one everyday, and run the risk of losing effectiveness if you miss more than one. I have used Loestrin and Depo before (not at the same time), and it is completely okay to switch from one to the other. Hope this helps. Good luck and best wishes :)