I've had this discussion with tiktok before, but I'm going to recount it here because I think it's relevant.
After crap support from HCPs in first few days, my DD had lost 13% of her birthweight at day 3. We were readmitted, formula/EBM top ups, discharged with good weight gain but no plan.
Rang NCT counsellor, who came round to my house the evening we were discharged. I was feeling very very fragile, but buoyed by the fact that at least she was now gaining weight. Wanted to get from mixed feeding to EBF, but had no clue how to do that, and no clue how to use formula in a way that supported the health of my DD but would do the least damage to my supply.
NCT counsellor was new to the job, and I suspect what happened next was a result of that.
She criticised the care that we had received. In my fragile state, I took that as criticism of me and the fact that I had allowed my DD to be weighed at day 3 (day 5 would apparently have been better), allowed formula to be used to top up, and restricted BF (3 hourly routine was feed for 10 mins each side, top up, pump for 20 mins each side, sleep for an hour; in the early hours I was pumping a second time instead of sleeping).
In terms of practical help, she wasn't able to answer my questions about how to get from mixed to EBF. Which, with tiktok's help, I now understand was fair enough - not her area of expertise - she's an expert on BF not mixed feeding. What I really really wanted to know was how long to BF for, how long to express for, how much to top up. No-one (NHS or NCT) was able/willing to give me that information.
The practical advice she did give me was to get a SNS and/or a doula, neither of which were financially viable at the time.
What happened was that I cup-fed EBM & formula top-ups for 5 more days, then decided to cold turkey and have her attached to me day and night instead of a pump. She gained no weight for the next 4 weeks. Having felt like I'd had a telling off the last time I spoke to the BFC, I didn't ring her but instead relied on my HV (who told me to eat more cheese. Wrong decision there!)
So at 6 weeks, we were back to formula top-ups and there we stayed until 10 months.