Yes, one Liberal leader said the issue of choice was an optional plank in the Liberal platform, and a later one said it was fundamental. That's the way politics works.  

People who want to publicly deny a woman's right to choose to have an abortion or not aren't persona non-grata, they just aren't members of the Liberal party.  I can criticize the Liberal Party about much, but not about that.  Does the Conservative Party not have fundamental policy planks?