What you describe could fit a number of different scenarios, some of which could be problematic depending on the specific circumstances in your particular case. The particular details matter.
If this is a scheduled in-person PR card pick-up (if it is for a PR card pick-up that will almost certainly be clear in the email you received), and you show up as scheduled, as long as you are CURRENTLY in compliance with the PR Residency Obligation (that is, you have been IN Canada at least 730 days within the five years as of the day you return to Canada, or otherwise in compliance based on credit for an exception such as accompanying a citizen spouse abroad), there should be no problem and you will likely be delivered the new PR card at that time.
If you are scheduled for an interview that is not attendant an in-person PR card pick-up, without more details it is difficult to discern the nature of this interview or whether it poses a potentially problematic situation for you. That said, here again the overriding key factor is whether or not you are CURRENTLY in compliance with the PR Residency Obligation (which again will be based on the five year period established by the date you return to Canada). Meaning, again, that as long as you are CURRENTLY in compliance with the PR RO, there should be minimal if any risk to your PR status. Of course, it is important that the information you gave in the application is accurate.
Note: it is likely your GCMS record has an alert or flag, which means you are quite likely to be examined more closely at the Port-of-Entry upon your arrival. And, for example, if you are NOT currently in compliance as of that day, the day you arrive at the PoE and based on credit for days in the five years prior to THAT day, you will be at risk for a 44(1) Report for Inadmissibility being prepared, and depending on whether you have H&C reasons, potentially a Removal Order issued (a decision terminating PR status, but subject to appeal). This is the main reason I referred to current compliance with the PR RO based on the five years preceding the date you arrive back in Canada. Technically, if you are waived through the PoE for example, the five years that will really matter, matter the most, will be the five years June 24, 2017 to June 24, 2022, meaning the date of your interview.
OVERALL: As long as you are currently in PR RO compliance (and the information in your application was accurate), there should NOT be any serious problems. Mostly you need to show up, and bring whatever documents the email says to bring.
