Still haven’t found any news on Unreal Updating their scheduler to properly utilize the P cores during packaging ( perhaps in UE5? Still on 4.27 )
In the meantime, a seemingly “hacky” workaround was to enable “Legacy Game Mode” in the BIOS of the computer. From what I’ve seen this option may not be available in all BIOS’, but essentially it turns the scroll lock key into a Turbo. Parking the E-Cores while enabled so that no processes will be started on them ( from tests it seems that processes that were already on the E-Cores continue to run )
Hopefully this is an option for anyone else that may be running into this issue!