Michael said your control configuration should remain untouched after the Beta 2 update, but he did recommend making a back up just in case. The CUSTOM.BINDS file can be found on your hard drive here:
C:/User/ ??? /AppData/Local/Frontier Development/Elite Dangerous/Options/Bindings/
You may have to toggle the 'Hidden Files' option to see it on your computer. Sorry but I am unsure how to do that. It all depends on your OS I believe.