When the 3/5 AND credit for pre-PR time rules take effect (they will probably be implemented at the same time but it is possible they might not be), the relevant time period will be the five years prior to the date the application is made. Days in Canada during those five years will count. Non-PR days will count as half a day. PR days will count a full day.
Days more than five years before will NOT count at all.
Thus, for example, if the changes take effect November 1, 2017, as of that day NO days spent in Canada (as either a PR or prior to becoming a PR) prior to November 1, 2012 will count.
If November 1, 2017 is the date the changes take effect, but the PR does not apply until December 1, 2017, no days prior to December 1, 2012 can be counted in the calculation.