Can I change "as of" dates for accounts not yet in the register?

As much I would love to help you, slyons2-mail-uma. but I'm little bit confuse. 

To do more digging into this, can you please provide me more details or screenshots about your concern? This way, I can outline the best possible resolution for you.   

For your reference on how to account register section works, you can click this article: Find, review, and edit transactions in account registers. 

I'll be right here waiting for your response and additional information's. Take care always!