NFC Compatibility Container

Hello everyone,,
New poster here

I have been playing around with PN532 chips recently, and have been using a MEGA board.

I see that the NDEF Specification states that a NDEF message can be 2^32-1 however it doesn't seem that I can set the Compatibility Container value to be more than 64k. Can someone explain where the value in the container size is the size of the whole message or the size limit of the entire message that can be exchanged?

Ideally I would like to set this larger for my purposes if possible but not sure how to.

As a note, I am not bound by the SRAM limits on the board with our work, I am however trying to understand the limits of how to express available memory in the CC container to represent the device as having more than 64k.

Thanks