The new framework for s. 11 (b) can be summarized as follows:

There is a ceiling beyond which delay becomes presumptively unreasonable. The presumptive ceiling is 18 months for cases tried in the provincial court, and 30 months for cases in the superior court (or cases tried in the provincial court after a preliminary inquiry). Defence delay does not count towards the presumptive ceiling.
Once the presumptive ceiling is exceeded, the burden shifts to the Crown to rebut the presumption of unreasonableness on the basis of exceptional circumstances. Exceptional circumstances lie outside the Crown’s control in that (1) they are reasonably unforeseen or reasonably unavoidable, and (2) they cannot reasonably be remedied. If the exceptional circumstance relates to a discrete event, the delay reasonably attributable to that event is subtracted. If the exceptional circumstance arises from the case’s complexity, the delay is reasonable.Below the presumptive ceiling, in clear cases, the defence may show that the delay is unreasonable. To do so, the defence must establish two things: (1) it took meaningful steps that demonstrate a sustained effort to expedite the proceedings; and (2) the case took markedly longer than it reasonably should have.