@LisaMcK, I am very optimistic at the moment but I just started working so only time will tell if I can keep it up, the only things I am doing at the moment is eating oats in the morning, drinking plenty of water, at least 3 litres a day, and making sure I eat during the day as well.
Are you using a double electric pump? In my pump bag I also have the following, although I am not taking any of them at the moment: Fenugreek capsules, Prolak tablets, brewer's yeast tablets and Alfalfa Tonic, all of them apparently increase supply and you can get them from Dischem. I am also trying power pumping this week (luckily it is a quiet week and my boss is very understanding), you can also try that, but so far I have not seen an increase yet.
This morning I did get a bit less than the past two days, I only got 180 ml from my morning pumping session where I got 270 ml yesterday, but I usually pump 120 ml at both of my sessions later in the day, so then I can leave 3 bottles for my son.
You can also try pumping for 10 or 15 minutes immediately after your baby nursed when you are home to see if you can get extra milk for the next day.
I am learning as I go, and hope to be able to keep my supply going. Also join the following groups on facebook, they have a lot of advice: "La Leche League South Africa" and "Exclusive Pumpers South Africa".
Let me know if anything works for you