The amount of light wont really hurt your plant. Light helps the growth process. All plants utilize a dark cycle to "rest" releasing some of its sugars and energy built up during the light cycle. Plants will still grow well with 24 hours of light but the will be taller and the potency mite drop a little bit.
It's possible that it could stress the plant and cause it to become a hermie, but there's no way to say for sure whether it will or won't happen. The Grower's Bible says to stick to whichever light schedule you start with, but I went from 18/6 to 20/4 with my current grow without any problems. Some will likely suggest to slowly increase the light each day to prevent stress, so maybe increase by an hour a day until you get to 24/0.
Yea that sound like a good idea to ease it into the change, i'm going to try that. Thanks for the advise.