I went back to work 4 days a week when ds was 6 months, same as you, OP. It was tough, but doable.
I fed ds immediately before dropping him to cm, pumped 3 times a day, and fed again on pickup. Sometimes, I had longer days that meant I had an earlier start or later pickup, and that meant 4 pumping sessions a day. He fed 2-3 times a night (no change there) and on demand during the days we were together.
I had a double pump and a mini fridge in my office to store bags of milk and the pumping kit between sessions. Each pumping session took about 20 mins to set up, express, and put away. The hard part was making sure I could get back to my office from meetings, etc. so many times a day. I would be very uncomfortable and leaky if I ran late.
I used the rule of trying to pump one oz for every hour ds was with his cm, plus one oz spare if possible. That came to 9-10 oz a day, which took me 3 pumping sessions. Turns out I don't have a huge storage capacity, so you might be able to get the same volume in fewer pumping sessions.
I was able to cut down to 2 pumping sessions when ds was 9 months old (the volume per day had gone down to about 7-8 oz by then anyway). Down to 1 session by 11.5 months, and stopped pumping by 12.5 months once he was happy on cow's milk.
DS is 18 months now and still bfing morning and evening 