When you prepare ERAS, you have to allow transcripts and Step scores to be released or no one will see step 1 and they won't interview you. But there is a second option that asks if you want to "auto-release" future step scores. If you have already received CK score then you have no option because you can't release step 1 and not CK. But if you haven't taken it yet or don't have your score yet, you can choose to authorize the release of future step scores at your discretion.
When and if you decide to release these scores, you just go back in ERAS and check a box and push submit again. Most programs set up a "continuous download" of your application. They usually don't print everything off until a few days before your interview so they should have it if you release before your interview. If you release after your interview, they will probably look at your app before they compile final rank list and see updated step score. So either way most places will see it, but you could always just email PC and tell them it's available if you want to make sure they see it.