I have a couple of random comments that may or may not help with your supply - it sounds like you are doing an awesome job - and you work full time, wow!
Anyhow, I noticed that as long as I nursed or pumped at least every 4 hours during the day and went no more than 6 at night without nursing, I would not ovulate - it was only when I began spacing out the feedings to more like 5+ hours in between that I began to ovulate.
Whenever my supply dropped, it came back in 2-7 days (depending on the reason) with frequent nursing or pumping. During the times when my supply dropped, I supplemented with food, like applesauce.
Lastly, Dr. Jack Newman says that nursing moms have the potential to exclusively nurse until age 6 months, some longer. You're not alone.
The only thing that you didn't mention (and I am impressed by your research - great job) is Domperidone. I took it for a year because my supply kept on dropping for various reasons. It took only 4 days and it worked very well. I don't take it now, and my milk production is just fine - I think I just needed the security while I learned about my body and breastfeeding. I ordered it online.
I am glad that you mentioned the calcium - when I was reading up on it, I read that it was a cal/mag supplement (at a particular ratio) that was needed to offset the hormonal effects of menstruation on lactation.