Should we brown the turkey early or late in the cooking process?

We’re doing a roast turkey inside a brown paper bag, but the question now is: Should we cut open the bag ⅔ of the way through the cooking process to brown the breast? We should have thought of using thermocouples and a DCS (Distributed Control System) to control the cooking process for the whole meal. Maybe someone else will do that next year. You-know-who.