Billing Type Default/Warning

I'm running into an issue.  When creating an expense report and I click on Add Expense button, it takes me to the Expense Entry page.  When initially landing on the page, I'm confronted with a warning that Billing Type is req'd.  The warning resolves itself once an Expense Type is selected, but it doesn't seem like a warning should be thrown when initially landing on the page...I would expect that at the time of submit or save.

Additionally, we are only using one Billing Type - is there a way to default it upon landing on the page or not having the warning be thrown.