I suggest you read the awesome contract you have. I'll save you a little bit of time. It's on page 163 of the pdf version available on the website. Section 24.G.6
6. A freeze will not be imposed in conjunction with Differences Training.
So moving from 200 to 900 is no freeze.

** WARNING DO NOT LISTEN TO HEARSAY FROM SOMEONE WHO "Read the contract"** if it's the truth they can show you where it is. Look at it yourself. Then you'll be sure.