Hi again,
IF you plan to do a short landing do it as soon as you can (while staying above the 6 month window) and once you're back you can apply for a passport via the tatkal scheme (if you can) or just a regular application.
You will need to plan your trip so that both your onward and return flights are well above the 6 months window.
Alternatively, if you can apply for a tatkal passport (know a class 1 officer and have other docs ready) do it asap and send in both your passports when asked by CIC along with a letter explaining why you're sending the two passports. This way your new passport will be stamped and the COPR will be tagged to the new passport (COPR mentions the travel document number). Don't renew your passport AFTER getting the COPR and before landing. That will be a blunder AFAIK!
P.S. I'm assuming you're from India "fromind83"

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