Firmware upgrade path

Hi,

I have two PS 6210X units sharing a RAID6 storage pool.

Both units are currently running FW 7.0.4 and i am looking to get them up to the latest version.

I am seeing on conflicting information about the upgrade paths. Can i go directly to V9.0.3 or do i need to go to 8.1 > 9.0.3

Thanks in advance.