Yea they are pretty strict on the CXC requirements (Even if you have tertiary level education, they still want to see the cxc results). I find that strange...
Five (5) is the requirement as listed and you must have the 5. (Math and English are the mandatory subjects). I have had friends that applied and received interviews with equivalent high school diplomas, so that shouldn't be a huge deal either... They also had tertiary level education. It is always advised to have some tertiary level education as more and more airlines will soon ask for higher education level in the future to progress. Cal list degree an asset!