The existing AROS source-code has been forked in order to speed up the development of its m68k branch. The reasoning of this choice is that AROS embeds at the moment a lot of code for different platforms (x86, ARM, 68k) which is not relevant in this case. Being able to remove all that unused code will ease development (shorter compile time, easier understanding of code), bring quickly improvements on the table and possibly improve performance of the bunch.
The Apollo team goal is to improve AROS 68k support and level up its compatibility with AmigaOS3 to the best state possible. Embracing that goal, some brave team volunteers started to maintain that fork and code is fully available on GitHub: EXTERNAL LINK
If you are interested into digging in it, complete and easy compiling instructions are available here: EXTERNAL LINK
To show and demonstrate improvements made, the Apollo team also started to work on a complete distribution based on it, called ApolloOS which can be downloaded and tested here in its last build: EXTERNAL LINK