Financial settlement overruled by court?

[GinismyTonic]

My ex has made an offer that I am happy with. My solicitor has advised that it may be a judge will overrule it if it is felt too low. He suggests my ex may have had bad advice. We are proceeding on the grounds of this offer which obviously benefits me but I just wondered if anyone had heard of judges doing this.
I am resident parent to a primary aged child and the ex main concern is getting out of the mortgage of which there is no hope if I take a lower offer.
Many thanks