As I understand it, Pre-Crisis there was Powergirl (girl who came from krypton in a rocket). Post-crisis, there was never a Supergirl who came from Krypton, but there were the other ones (matrix, Linda, etc) who were modeled after someone else. Now there is the current Supergirl who came from Krypton in a rocket and has adopted the mantle of Supergirl.
My first question is, post IC those previous post-crisis SG's are no longer in continuity. But right before they were wiped out, before IC, did anyone tell current SG that there were SG's before her?
Second, who were the other Pre-IC SG's (matrix, linda) modeled after?
And finally, who was the Supergirl that died in COIE? In the issue with the famous cover of Superman holding her body?