I'd love to hear your perspective here, I'm interested.
If you're really passionate about something, it's not going to die just because you spend some time on other stuff.
I think the "strike while the anvil is hot" phenomena is largely because of survivorship bias. Most of the time, if you drop an idea after 2 weeks, you're not going to come back to it. But that's because most ideas that are only 2 weeks old aren't very good and should probably be abandoned anyways. While if you've been turning the idea over in your head for 2-3 years (as Eve had been, before I started working on it), another 18 months isn't going to make much difference.
I'm blessed with an ability to focus very sharply on one idea and do great things with it, but that blessing is a curse too since while I'm focused, I tend to ignore all the other stuff.
On the other hand, I've also got a bad habit of starting many more things than I can finish. As a result, most of my ideas have been on the backburner for some time. Eventually, they have to become the focus, but being on the backburner doesn't mean they're gone (though some of them certainly do change and evolve and even die while on the backburner... but I don't get too attached to a single idea).
However, that does not necessarily mean that you completely stop working on your startup. While being committed is important, there is a right time for everything and it may not be the best time to drop out of school... suppose an year down the line, you change your mind- it will be a lot harder and for you to get into good universities. The risks vs. benefits at this stage may be out of whack.
The important thing is that the idea should not die and should always be on the backburner until the time is right and you have the matured view of the world [and how cruel it can be] to make the whole scheme of things to work in your favor.
Just my 2 cents...