That's in this bill before you, and that's right. Child benefits, like some other income benefits, work on a July to June schedule. In July 2018 it will be based on your 2017 income. Both the maximum benefits and the income thresholds will be indexed at 1.5%, which is the indexation that applies to the 2018 tax year.
Evidence of meeting #145 for Finance in the 42nd Parliament, 1st Session. (The original version is on Parliament’s site, as are the minutes.) The winning word was rate.
A video is available from Parliament.