None of those numbers are a surprise to me. I fully expect the Model 3 to maintain the #1 spot every month this year. In fact, I don't expect it to be de-throned until something like the Model Y comes along.
What will be interesting to see is the Model 3's effect on EVs like the Bolt. It could have no effect, and GM simply controls Bolt sales via production and distribution. It could hurt Bolt sales, as the queue shortens and more people are willing to wait for the Model 3. Or it could have a "rising tide raises all ships" effect, and help all EV sales by increasing awareness. 2018 will be an exciting year for EV sales, whichever way it goes.