Firmware for 256kb ender 3 pro?

Early ender 3 pro had a RET6 cpu with 512kb flashmemory, lately creality switched over to RCT6 cpu which only got 256kb flashmemory.

Using a firmware made for 512kb on a 256kb can cause issues so my main question is, is marlin firmware made to work with these newer motherboards with only 256kb flash memory?

All of the builds for Creality boards are 256Kb.