New XB7 Gateway

I currently have gigabit internet service using a SB6 gateway, and have been having problems for a while now with the speed that I'm getting, my xfinity voice not working, and the router losing internet connection altogether until I reboot it (which has been happening more frequently now). I normally have between 30 and 40 devices connected through a mix of wifi and ethernet at any given time. I also have 2 pods installed. I've been looking into going back to using my own modem/router or just changing providers altogether. I recently read about the new SB7 gateway, and was excited about trying it, as it would probably  fix the issues I'm having. But when I called, they told me something about waiting exactly two weeks from when I called for an email and then I'd be able to get it.  I really don't understand the situation. In the past I've never had any issues upgrading equipment, it would just be sent to my home and I'd return the old equipment. Can someone explain the situation to me? Is there any way to upgrade as I've always done? I've tried troubleshooting the issues I'm having with my SB6, and there's no point in replacing it with another SB6 when the SB7 is out. I appreciate any help I can get. Thanks!