Per the company email, the new 175s will be DFW based.

DFW selected as Envoy’s initial E175 operating location
Dallas/Fort Worth (DFW) has been chosen as the initial operating base for Envoy’s new Embraer 175 (E175) service. “We’re proud to be the first American Eagle carrier to operate the E175 in DFW,” said Jim Winkley, Vice President E175 Program. “We’re confident that this aircraft will be very popular – with both customers and employees.”

The first E175 will be delivered to Envoy in November and will spend quite a bit of time flying around the DFW area after arrival. “The first airplane will be very busy, well before it carries the first revenue passengers in 2016,” added Jim. “Our crews will be flying the aircraft right away, gaining their Initial Operating Experience on the new aircraft type. It will definitely become a ‘frequent flyer’ in DFW!” Envoy’s DFW airport team will begin to see a number of preparations in the coming months, such as gate preparation, new tooling, delivery of E175 parts and training.