I can't answer your question, but wanted to add something.

You mentioned badly cracked nipples & bleeding last time? I'll just make a suggestion. Silicon nipple shields can help. They aren't good for long term use, but I used them while my cracks & thrush healed & they were a God send. I only used them for 2 days, but they gave my nipples the break they needed to heal, while I still fed DS as much as he wanted.
Nipples do heal quite fast, so I wouldn't recommend using them any longer than about 2 days, but they truly did help me. Maybe they'll be worth a try in the middle of the night. The step before formula. Baby still needs to put in effort to drink too, so him/her becoming confused shouldn't be an issue
Only if you feel comfortable using them though