Revature Webinar: would it be an issue if I can't attend until a week (or two) after the initial screening phone call?

I am lucky to have been invited to Revature's webinar, after submitting my resume through their website, and speaking with someone at Revature (just confirming the basics of my application). They told

I am lucky to have been invited to Revature's webinar, after submitting my resume through their website, and speaking with someone at Revature (just confirming the basics of my application). They told me that the next step is to attend a webinar. Unfortunately, it only meets when I tutor (as part of my grad school assistantship). I have emailed the person who runs our tutoring center to ask what my options are, but I'm unsure how soon this time-off request will be approved. If I am unable to attend until a week or two from now, will this be an issue? Is there someone at Revature whom I should contact? I unfortunately didn't think to ask during the phone call about someone to contact if I had future questions.