IF + long and Stress packed day = weight gain (esp stubborn fat areas)
You could cut back on the IF and just go the warrior diet way of small eating during the day and bigger meal at night (not overdoing on the calories of course). Might also want to try sipping BCAAs in water, may help curb cortisol while doing IF and during stressful times.
Seeing how the brain is a glucose hog, it's demands for energy during a long workday especially when stressed tax the whole body.
Of course sleep plays into that whole stress-recovery cycle of hormones as well.