Just to clear this a bit more. When calculating absence for PR your absence from Canada when you left on the first of the month and returned on the second would count as 2 days out whereas citizenship calculator counts such as 0 days out
Not actually. The method of calculation for both has been the same since June 2015.
And, in particular, the PR Residency Obligation calculation has been based on days actually physically present in Canada for nearly two decades, so any part of a day in Canada counted toward compliance with the RO, including the day the PR exited Canada, and the day the PR returned to Canada. An overnight trip to the U.S. counted ZERO days absent.
Since June 2015 it has been the same for the Citizenship presence calculation.
Prior to that, for citizenship there was a "residency" requirement and CIC (before name change to IRCC) counted ONE day present for either the day of exit or day of return. (In effect, the old rule for CITIZENSHIP counted the number of midnights in Canada as number of days present; number of midnights abroad as the number of days absent.)
My view about
margin over the minimum: for the very, very confident, at least ten days or more is a prudent minimum margin over 1095. I tend to think at least a full month is the wise approach.
Apart from that majority of very confident applicants, how much longer to wait is a very personal decision for which the prudent approach depends on each individual's own situation. For a few, waiting may be more about moving toward better circumstances than it is about the number of days (I waited nearly TWO years past the date I TECHNICALLY met the requirements, due to personal circumstances largely related to self-employment selling services abroad.)
In this regard, it warrants remembering that total stranger bureaucrats will be making decisions about how it goes, including whether or not any non-routine inquiries are needed to sufficiently verify the applicant met the actual physical presence requirement. Prudence dictates allowing them a buffer of days to make those total stranger bureaucrats more comfortable reaching favourable conclusions about the facts.
Yes, 1095 days meets the requirements. Not a day more is necessary. But IRCC does not have a crystal ball. The burden of proof is on the applicant. IRCC has a mandate to VERIFY the applicant meets the requirements. Waiting longer to apply can actually result in taking the oath sooner . . . and at the least generally allows for more peace of mind along the way.