You're correct. There are three working groups: data monitoring, which is looking at the existing data and new data that has come since the proposed decision by Health Canada; the mitigation working group, which will work closely with the data monitoring as the data monitoring should be able to pinpoint some of the crop uses, and from there the mitigation working group will assess if there are mitigation measures that could be taken into account and get to an acceptable level; and finally, the alternatives working group, which you just raised.
That work, the work plans, and any data will be submitted to PMRA before the end of the consultation period, but the work will continue past the consultation period because there's the intent of doing further data monitoring.