ATSAM3X4C compatibility?

Hi all, I am working with an individual to design a board that implements the Arduino Due pin mappings and functionality. My question is, in light of the chip shortage, does anyone know if I were to utilize the 100 pin 3X4C processor instead of the 3X8E, what the compatibility with the Arduino IDE would look like?

AFAIK, there is no shortage for that chip at Microchip. I could order 600 ATSAM3X8EA-AU or 1840 ATSAM3X8EA-CU this morning !

I did find them in stock. However I’m still curious about the ability to use the 100 pin variant. I did not read all 1450 pages of that beast of a data sheet but as far as I can tell, it’s the exact same chip just without the additional flash memory controller and maybe some other high speed bus functionality. It doesn’t appear that the arduino schematics even utilize the additional pins in the cpu.

The C variant is nearly 1/3 to 1/4 the price as well so how difficult would porting due bootloaders to the C variant be, if possible at all?

Sam3x datsheet, page 2:

16 Kbytes ROM with embedded bootloader routines (UART, USB) and IAP routines