I thought this information may be helpful for anyone else struggling with this issue. I managed to get a customer service rep who escalated the filing issue. This is what she said in an email to me today
Thanks for taking the time to speak with me the other day.
I did escalate the 600S form and availability issues you (and others) were having. I now see the form is scheduled to be updated and available on 03/15. I understand the time crunch this puts you under and I do apologize and want to let you know you do have until 11:59pm PST to efile the returns.