There was NO police certificate required for citizenship applications made prior to a June 2015 version of the application form. Applicable prohibitions time period for foreign convictions continues to be FOUR years. Thus, it is not likely there will be any change in who must submit a police certificate (except the item will likely be renumbered given other changes in the form).
Explanation:
Again, there was NO police certificate requirement for citizenship applicants prior to June 2015. What changed was the addition of a prohibition provision in the
Citizenship Act, Section 22(3)(a), which took effect in May 2015, adding the prohibition for convictions outside Canada in the
four years preceding the date of the application. See this at
http://laws-lois.justice.gc.ca/eng/acts/C-29/page-6.html#docCont This provision, this prohibition, has not been amended by any subsequent legislation.
In particular, the prohibition time period continues to be the preceding
four years.
Thus, a change in the criteria for who must submit a police clearance with the application is NOT likely.
Some change is nonetheless possible. Indeed, IRCC could remove the police certificate requirement altogether, since all applicants must otherwise affirm they have no convictions abroad in the preceding four years. OR IRCC could revise the criteria. So, applicants need to wait to see what the new form actually includes and follow the new instructions.
Odds are high, however, that the current police certificate instructions and requirement will still apply and be included in the new form, which should be available by some time on October 12, perhaps late in the day October 11 (noting that when the transition to the 4/6 rule took effect, June 11, 2015, as I recall it took a little longer than that to get the new presence calculator online).