The general rule of thumb lately has been that you need to grab the flights as soon as they are released -- prices do not seem to go down over time, they go up.
As for the next release, Southwest publishes this on its site.
And is it easy to fly out of Buffalo? We're converts now. The airport is easy to get to, there are plenty of places to stay if you want to go the night before, parking is easy, security is simple. And even with airfares at levels that the locals complain about, it's still far cheaper than flying out of Pearson.
When we were returning from MCO early last month, the flight attendants did a poll and asked for a show hands from people who would be crossing the border after we landed. Everyone onboard had their hand in the air!