I just realized the card I used to buy a OW ticket on Jet has been compromised/replaced. How strictly do they enforce this rule:

Security Requirement
. The card used to purchase the tickets will have to be produced at the time of Check-in.
. If the holder of the card is not the passenger, then the passenger should possess:
a. A photocopy of both sides of the card, which will have to be self attested by the card holder authorising the use
of the card for the purchase of the ticket. For security reasons, please strike out the Card Verification Value (CVV) code on
the copy of your card.
b. This photocopy should also contain the name of the passenger, the date of journey and the sector on which the journey is
made.
The above document MUST be produced at the time of check-in. If the passenger fails to comply with these conditions, Jet Airways
reserves the right to deny the passenger(s) from boarding.
The details mentioned above do not apply for Net Banking / Cash Card and Cash on Deliver

You can cancel the card at your bank, but still keep the physical card to show at check-in. Should be OK.

the card is long gone, but I ended up cancelling the booking - which required 3 digit code and expiration date of old card, but it was ok with random pin :-)

I then booked the same flight taking advantage of the sale in place - even after cancellation fees I still was in the plus :-)

Took overnight though for me to book the same flights, as it was complaining about duplicate booking for a while.

i've taken over 100 flights a year with jet over the last 6-7 years....never once have i been asked for the credit card used for booking....