I think the fastest way to get a definite yes or no is to open a ticket with NetApp.
 
The documents for ESERIES Controller upgrade are covering information within the same series:
E2800 & EF280
E5700 & EF570
 
There is no information on upgrade/headswap between EF280 to EF570.
 
I have a strong feeling this is un-supported (Even though Chassis dimensions & Shelf drive ports seems idential for EF280 & EF570).
 
Thanks!