Is there any room for prequels in the MCU?

So I read once one time that Disney has had Marvel plan out the MCU for the next decade or so. Every year we have 2 marvel movies, and now with the spidey reboot, for about 3 years I think we may even have 3. So it's clear that the MCU, as a marvel earth in and of itself is chugging along with its story.



But, with it doing so, does it completely rule out any potential prequel films? They're so busy trying to keep the story progressive I don't think there will be time to ever have any prequel films for main characters in Marvel.