I see this both ways. I believe it is "wrong" to call kids after they publicly commit to a school and when my son was recruited he would tell coaches he already committed to xyz school and every coach backed off and said "oh sorry I did not know that, Coach ABC is a great guy, good luck to you". But I do think it would be permissible to say "If you change your mind please call us, we were thinking of a 40% scholarship for you, so if that makes a difference to you let us know"
Some kids commit early so they do not have to deal with recruiting during their senior year, but take less than they could get elsewhere. Just my thought.