What does the change in law mean to me?

Because the new law gives donor-conceived people the right to know your identity once they reach 18, they could contact you. Not all donor-conceived people will want to do this.
You have no legal responsibilities to any child created from your donation. The person who received your donation (and their partner if they have one) will be the child’s legal and social parent(s). You will not be named on the birth certificate and have no rights over how the child is brought up, nor will you have to contribute financially.
Knowing about their genetic heritage helps people to make sense of who they are. This is why you are asked to give information about your family and medical history and to write something about yourself that a donor-conceived person can read when they reach 18.