“Section 56(4) differs from s. 33(4) Family Law Act in that s. 33(4) operates even when there is a valid and subsisting domestic contract but the provision respecting support results in unconscionable circumstances: Scheel v. Henkelman, [2001] O.J. No. 55 (Ont. C.A.).
In general, the doctrine of unconscionability with respect to domestic contracts under s. 56(4)(c) Family Law Act focuses on whether or not there were unconscionable circumstances surrounding the formation of the contract. Under s. 33(4), the focus is on the results of the waiver of support: does that waiver result in unconscionable circumstances when the agreement is triggered by separation: Toscano v. Toscano, 2015 ONSC 487 (Ont. S.C.J.).”