Thanks! Good point re: bottle being colder. She used to want it super hot or not at all and we've never tried otherwise. It might have changed! Temperatures are meant to soar again by the wkd so we'll do that.
But in the meantime: I don't want to jinx it but... I think we're out of the phase!!! After two months, finally! It's the fourth day today and things seem to go better and better. She's been waking up for only one feed and sleeping more soundly around it. Good feeds have returned during the day. Hurrah!
In case someone reads this thread in the future, looking for help, I'm listing below what I've been doing but, truly, I think she's mostly grown out of it by herself:
* did a lot of skin to skin for feeds, which seemed to encourage her a bit (although it became a mess when weather became hot)
* brought her comforter back with us for the bedtime feed, which helped her relax and focused her attention
* sent dad to try and resettle her with cuddle (and water when super hot weather) first at each night waking before midnight + I tried to resettle her first first before feeding after first feed of the night + would NOT feed between 4.30 and 6am (her wake up time) but tried to resettle to sleep. It's quite obvious if it's hunger with her as she just won't accept to be resettled and will have a distinctive cry escalating so I'd immediately feed in that case. But she accepted to be resettled more and more. She also surprised me at dawn as I thought hunger would keep her awake but she ultimately went back to sleep, which encouraged appetite for her first feed of the day. We've been having only one feed around 11pm with a few resettling around it and wake up at 5.15/5.30 Saturday-Tuesday, Wednesday one feed at 11.30 with no wake ups around it and up for the day at 6am, and today one feed at 0h30 (7h45 since last feed, yeah!) and sleep until 7.15am with only one 2seconds resettling at 6am (which NEVER used to work).
She now feeds during the day morning + bedtime + before/after each nap. I make sure she doesn't feed to sleep by changing her nappy and putting her in her sleeping bag after that. It's not "textbook" but it works and I expect she'll drop some feeds as she gets older or during a new phase. It's fine for now.
So just a message of hope: it DOES pass, even if it lasts for 2 MONTHS like it did for us. I'm so glad I didn't go down the 'gentle' sleep training route suggested by the HV.
Thank you so much for your support here! It got me through it