Weaning off pumping

Da

I'm a bus driver and work 5pm-1am and every break that I take to pump (roughly an hour because of drive time to and from my route and pump time) is unpaid. I make 20.00 (not trying to brag about how much I make cause I'm still broke AF because of debt) and hour so both times I'm pumping I'm losing 40.00 a day, so almost 200 a week. We already supplement formula and have since he was born so that's not an issue, but I am worried about losing my supply if I stop pumping while at work. I saw somewhere that as long as you empty your breasts 6x daily it should maintain your supply, does anyone have experience in this area and know if I, in theory, can maintain my supply enough to nurse him during the day even if I don't pump between 5&2?