we have multiple different builds for our phone, dl17, ec03 and ec09. All of these builds utulize different modems, kernels, radios, systems, etc. If you were to flash this package ofer an ec03 or dl17 build it would only upgrade the system recovery and kernel.. making the phone either not boot, or very unstable.. So, by ensuring it is on a previous ec09 build it will prevent any potential issue. If your coming from a stock phone that is completly up to date then you simply need to flash this overtop.
If you are coming from another build, i recommend grabbing the complete update first then flashing this over to remove all of the bloat.
Let me know if you aren't able to download it.