CoPR is in NO way a Travel Document. After once used for the landing, it does not itself document authorization to enter Canada. It is a document which, however, Canadian PoE officers will examine and consider as evidencing the traveler's status as a PR, subject to proof of identity (passport usually; refugee travel document for protected persons). So at a land-crossing PoE it will facilitate the entry process when a PR does not have a PR card.
Note, a PR is statutorily entitled to enter Canada. No particular documentation is necessary. But of course proof of identity and status is necessary to establish one is a PR who is entitled to enter Canada. Proof of identity at the PoE will usually suffice, since CBSA can establish the traveler's status based on the traveler's identity. However, while a passport ordinarily will suffice to show identity and thus status, in the absence of a PR card, presenting a CoPR tends to make this process go more smoothly and more quickly.
Otherwise, the CoPR is an important document that does not, itself, expire, and should be kept safe for life (at the least until one becomes a citizen and beyond that until one reaches the age to collect government pension benefits, as the CoPR is the key document necessary to show date of immigration which is key to calculating some of the benefits a person will receive).
The date by which the landing and becoming a PR must be done is indicated in one of the various fields of information in the CoPR. Some confuse that with an expiration date for the CoPR. Again, the CoPR is an important, valid document to be safely kept for life. In the meantime, IRCC can request a copy or to examine the original attendant processes such as citizenship applications and PR card renewal applications.
Note, a PR is statutorily entitled to enter Canada. No particular documentation is necessary. But of course proof of identity and status is necessary to establish one is a PR who is entitled to enter Canada. Proof of identity at the PoE will usually suffice, since CBSA can establish the traveler's status based on the traveler's identity. However, while a passport ordinarily will suffice to show identity and thus status, in the absence of a PR card, presenting a CoPR tends to make this process go more smoothly and more quickly.
Otherwise, the CoPR is an important document that does not, itself, expire, and should be kept safe for life (at the least until one becomes a citizen and beyond that until one reaches the age to collect government pension benefits, as the CoPR is the key document necessary to show date of immigration which is key to calculating some of the benefits a person will receive).
The date by which the landing and becoming a PR must be done is indicated in one of the various fields of information in the CoPR. Some confuse that with an expiration date for the CoPR. Again, the CoPR is an important, valid document to be safely kept for life. In the meantime, IRCC can request a copy or to examine the original attendant processes such as citizenship applications and PR card renewal applications.