If a PR TD application has been denied for not meeting the PR Residency Obligation, there is an inadmissibility issue. The decision itself is a determination that the PR is inadmissible due to the breach of the PR RO.
"Inadmissibility" is a status and does not directly mean the individual will not be allowed to physically enter Canada. And, indeed, so long as the individual remains a PR, that individual is entitled to physically enter Canada, even if he or she is "inadmissible."
After a PR TD application has been denied, that individual remains a PR for the time period in which an appeal can be made. That is currently 60 days. If an appeal is properly made during that period of time, this individual remains a PR for as long as the appeal is pending. However, during this time period the PR has inadmissible status, which again does NOT preclude entering or staying in Canada, but also cannot gain credit toward PR RO compliance.
Thus, if a PR who has been denied a PR TD can nonetheless travel to and arrive at a PoE into Canada, before the expiration of time period in which to make the appeal, or while an appeal is pending, that PR will be entitled to physically enter Canada.
For clarity, the appeal I am referring to is the appeal by right to the IAD, which is an administrative or quasi-judicial process. The IAD acts like a court, a reviewing court, but it is not a formal "Court" as such.
In particular, I am not sure what "appeal period of 30 days" you are referring to (last I looked, the time within which a denied PR TD may be appealed is 60 days).
I am also not sure what "Court" you are referring to. (Again, an appeal of a PR TD takes the matter to the IAD.)
If, for example, you are referring to a case where a PR was denied a PR TD, made an appeal to the IAD, and then lost that decision and you are referring to the time to make an application to the Federal Court for judicial review, I do not know the individual's status during that period of time.
Being "stopped at PoE:"
All travelers are stopped at the PoE, even though briefly (very briefly for Nexus travelers for example, barely a stop at all but sufficient for electronic chip to be read). The nature and duration of the stop varies considerably.
The most common and biggest distinction involves a referral to Secondary, which is an examination following the PIL (Primary Inspection Line) step. The PIL exchange (usually at booth if the crossing is made by car) is brief for most, little more than presentation of Travel Document to show identity and status, some perfunctory questions, then a waive through. If the PIL officer identifies more complex immigration issues, there is a referral for a Secondary Examination.
Anyone, everyone, can be referred to Secondary for a further examination. Including Canadian citizens. Once a traveler is properly identified as a Canadian, however, that person is entitled to enter Canada. PRs are Canadians, and thus once identified as a PR they are entitled to enter Canada. Even if they are "inadmissible." (Again, "inadmissibility" is a status; inadmissible PRs are still Canadians, still entitled to enter; inadmissible FNs, in contrast, have no right of entry and thus their inadmissibility will ordinarily mean they will not be allowed to enter Canada, not without some kind of waiver.)
Nonetheless, the CBSA immigration officer in Secondary can conduct an examination of a PR regarding compliance with the PR RO. For a PR determined to be in breach of the PR RO, thus inadmissible, a 44(1) Inadmissibility Report is issued, to be followed by a Departure Order. Since the PR has a right of appeal, the PR remains a Canadian and can then enter Canada. The time within which that appeal needs to be made is 30 days (as I recall). That individual loses PR status at the end of that time unless the appeal is made.
For a PR who already has a PR TD denied, there will likely be a referral to Secondary, the event will be documented in FOSS, the PR will probably be advised and/or admonished about his or her status. If no appeal has been made yet (and it is still during the time in which the appeal can be made), the PR will likely be admonished that PR status will be lost and the PR must depart Canada accordingly. In this scenario, it may be possible that a 44(1) Report and Departure Order is issued, despite the fact that a PR TD application has already been denied. If the PR has already made the appeal, before arriving at the PoE to enter Canada, the PR will likely be informed or admonished to some extent about his or her status.
Note: even if the PR is waived into Canada without a Secondary examination, if a PR TD application has been denied the PR must appeal that decision or PR status will be lost. Once a PR TD is denied, to keep PR status the PR must appeal and win the appeal. Thus, even if the PR comes to Canada and is waived to enter Canada, this is not a situation in which the PR can then live in Canada for two years and cure the breach of the PR RO. In this scenario, PR status is lost unless the PR appeals and wins the appeal.