As you can see, I was so taken by your mention of lactose intolerance, that I am linking a few articles. You know LOTS of this stuff already, but I wanted you to be aware that true lactose intolerance in infants (hypolactasia) is very rare, and is not a reason to wean (some MD's say this!). You can read about it more in these links:
Is there ANYTHING unusual in your diet that could be affecting your baby? Any medications?
It is recommended that if you are considering removing cow's milk proteins (all sources!) from your diet you give it 2 weeks before you gauge the results. It could take that long to move all from your system. I can understand how daunting that may seem if these products are a large part of your diet. It is something to consider seriously.
I don't honestly know what to expect after having blood in stools. I can't find anything in my resources, but I will check.
Yes, you could just pump a full feeding when dh gives the bottle. I would suggest instead of doing minutes/feeding that you watch the baby, not the clock. If you are experiencing oversupply and are block-feeding, then you do need the clock somewhat! But not when baby is nursing. Always allow her to "finish the first breast first" before switching. This could mean 10 minutes or 45 minutes. Depends on the baby!