I hope it works out for you. I appreciate your worry about losing productivity, that's my worry too - I used to get so much done!
I go back to work tomorrow, and will be having to express at home and work. Other than productivity, I am mainly feeling worried about being able to express enough for him. He still eats like a machine, 14 times a day and he's 6months old! He's a happy and healthy boy though!
Good luck, I hope you can work it out.