Question: Using Alternate keys when inserting, updating entities

[swidz]

I wonder if it is possible to send POST (inserts) using alternate keys on navigation properties like this:

url: /api/data/v8.2/contacts
method: POST
body: {
	"firstname" : "john",
	"lastname" : "smith",
	"parentcustomerid_account@odata.bind" : "/accounts(blg_alternatekey='blg12345')"
}

I am currently using class model which is converted to dictionary by standard functionality so the json being generated is like this

url: /api/data/v8.2/contacts
method: POST
body: {
	"firstname" : "john",
	"lastname" : "smith",
	"parentcustomerid_account@odata.bind" : "/accounts(00000000-0000-0000-0000-000000000001)"
}

Would it be possible to still using class model but force to use alternate key instead of navigation property's entity key ?

Regards,
Sebastian