What I mean about days reverting to 0, I'm talking about the consecutive days outside Canada. When I return to Ireland on Sunday, will I automatically be allowed another 1095 consecutive days outside Canada? I'm fully aware of the 730 day rule and PR card expiry, I'm just concerned about getting back into the country if a job offer comes through after March.
There is no consecutive 1095 day rule. It is the grand total number of days (consecutive or not) you are allowed to be outside Canada during your first 5 years as a PR or any 5 year period after that. You could have used up your 1095 days in one long stay outside Canada or with many short trips.
1095 days = 3 years and 730 days = 2 years so if you have been outside Canada for 1095 days total, you have already used up your whole 5 year allowance. That means in order to meet the residency requirements, you must stay in Canada for the next 2 years. If you were allowed to leave for 1095 days and then come back, spend a day and leave again for 1095 days, when would your 730 days of stay be?
However, it doesn't seem to be too hard to get into Canada even if you don't meet the residency requirements. They might give you a lecture but they don't seem to report people very often. If they were to report you, you could lose your PR. If you get in, as I said above, don't apply to renew your PR card unless you have your 730 days in the previous 5 years. Your PR card can expire and it will not affect you if you are in Canada but if you apply early, you will have problems.