Any entry exit won't be issue until you became later on all entries and exit need to be tracked diligently while applying for citizenship to fulfill RO...I pointed out that issue as soon as i have received the CoPR, however i havent highlighted that to CIC, because i dont want to do that. I fear it may cause delay in my PR card processing.
Aslo, that date issue is not a critical factor to be corrected, it wont not cause any trouble for me.