Here's the workaround that still works, posted by a fellow user, and has worked since around 2:20AM ET:
Using the verizon app, on the "shop" page, touch the magnifying glass in the upper-right corner. In the automated search, type in: iPhone 7 Plus
The automated chat will respond with a "Take me there" link. Click on that and customize your device! I put my order in at 2:43AM ET and got:
Apple® iPhone® 7 Plus 128GB in Black
Deliver by 09/23/2016
$419.99