In a Chase PC (within the same reward system, say CSP to Freedom Unlimited where both are UR points), you get issued a new physical card. The card number will remain identical. The CVV will change, and probably the expiration date. Your credit report will not show any change. You will get a revised terms and conditions for the new card. Use the old card until you get the new one.

In your Chase Login, the card image will change before you get the new plastic. The points will stay there. If you prefer, you can transfer the points from the CSP to the CSR before you do the PC.

Trivial items: The Freedom cards are plastic not metal. If you change from the the CSR/CSP, the 800 number on the back of the card is not the same. There are reports it routes to an offshore call center.