My estimates were all based on having $340k-$350k in my accounts by my birthday, and I'll still be in that window even if the market slows down significantly (I'm currently getting 15-20% returns and budgeting for 9%).
Of course, the world has to throw a curve ball. The recent stock market "corrections" over the last couple of weeks have, of course, knocked off something like 10% of the value it had. I haven't taken quite that much of a hit, but I'm now down $15k in my accounts than I was about a month ago, about a 5% loss. Now, that's not huge, but it throws off the numbers I was looking at. It also isn't necessarily done: the markets are down 300 points at the moment, though that's less than they were down a few hours ago.
I'm probably still okay. I mean, I'm making a lot of assumptions about the future - there's no choice - but most are fairly reasonable. I always assumed a 7% average annual return over decades; individual yearly fluctuations don't matter much. I also have to assume I'm keeping my job part-time for two years of school and forking over $22k twice (what a UC would cost, roughly and accounting for taxes and deductions). I also assume that, coming out of college, I can get a job making slightly more than my part-time here would pay.
Based on all that, I'll still have over $2m in the bank at 65. But that's assuming the market settles down and has something close to a 7% average growth for the rest of the year; that's not guaranteed, but it's also not unreasonable. If things get worse, well, I'll still be okay to a point, but it might mean having to pump in even more money once I come out of school.