I think you need to keep two things firmly in mind -
whatever you do, you can't stop the move from being distressing; don't feel guilty about that
and
your LO can't tell the time yet.
I am by no means an expert, but I believe that at these young ages, routines are less about doing certain things at certain times (as they can't tell the time) but about certain sequences, so, x happens after y, then z. These sequences lead to expectations being met. When expectations are met, we feel positive.
So, stick to these sequences as much as possible.
However. If your LO's expectations are that his needs won't be met; that he will have to wait, suffer, be anxious, be hungry, and won't get what he needs until a period of suffering has gone by - then I feel that you should NOT meet his expectations (that he will need to suffer, then will get a bottle), but rather meet his needs - thereby hopefully starting to change his expectations.
You need to be aware though that this will most likely completely overthrow the clock schedule, so you will need to be flexible enough to be able to stick to the sequences despite things falling at odd times. That's one important thing that kind of 'locked us in' - we couldn't (and still can't) go out for long times as we can't trust the clock - we're following the sequences and so always need to be ready, whatever the time is.
If you are unable to deal with unpredictable timings, for whatever reason; and this would make you unable to meet his need for predictability (of sequences); then perhaps (painfully) keep the clock schedule up initially, giving you all some time to get used to each other, to learn to 'read' each other, and then make this the first change you undertake once you are all a bit more settled.
Also, with regards to 'unhealthy' things it is a bit different. I'd say, who cares if he gets entirely too much sugar (just an example) - if he is used to having sugary things and takes comfort from them, then let him have them. When he is settled and attached, you can always start phasing them out later. But for now, easing the move and keeping him feeling secure in his expectations overrules the need for 'health' in that sense.
This is based on our recent (and ongoing) experience with a very young LO. LO's FC stated that LO must be 'made' to finish each bottle, or LO wouldn't last to the next feed. We had misgivings about this (recommendations are to never make babies finish their bottles but to let them decide themselves when they have enough) but as we couldn't yet properly interpret LO's behaviour (is LO taking a break from feeding, does LO just need winding, or has LO actually had enough?) we initially went along with this. However, despite making LO finish the bottles, LO would be desperate for the next bottle after 3 hours maximum, often even sooner, rather than the steady 4 hours that LO used to 'last' at FC. So we fed LO whenever we felt pretty convinced that LO wanted a bottle. I believe that LO wasn't 'hungry' as such, but desperate for comfort due to new place, new faces, new everything; and wasn't yet able to derive that comfort from us in other ways. Feeding LO every three hours (or so) then caused timeframes to get very short - LO was used to certain sequences of sleeping, waking, nappy changing, feeding, bathing etc. and these sequences now kind of had to fit into 3 hours rather than 4 ... causing all sorts of follow-on disruptions of the clock schedule, and meaning that bedtimes/morning waking times etc. were different every day. We went with the flow (good thing no-one had to be anywhere at specific times!) but stuck to the 'sequences' as much as possible.
Oh, FC also stated that we mustn't make eye contact when feeding LO as that would distract LO and LO wouldn't 'get on and finish the bottle'. This is an expectation that we consciously decided NOT to meet - we felt that LOs need for eye contact and closeness/intimacy during feeding, particularly when building attachments, overruled LOs need to have the expectation 'no eye contact during feeding' met. So from day one we sought eye contact during feeding.
Over about two weeks, LO's need for feeds gradually relaxed back into a (more or less) 4 hour schedule, and is staying at that (for now!), despite us now no longer 'making' LO finish each bottle. LO's need for sleep/ability to sleep, that's another story that we're still working on! LO was described by FC as a baby who 'sleeps all the time' to the extent that there was not much point in any sort of introductions, as we would just be sitting around gazing at a sleeping baby. Well, babies change... particularly if they experience a traumatic move.
Hope this helps. Remember, your LO will not be the same child, so to say, as the LO who the FC looked after. Your LO will have the additional experience of losing everything he knew and being moved to a completely new environment. So, even after only a day of being home, YOU will know your LO better than anyone else, including FC. FC never knew this 'new' post-move LO. You do. And every day you will grow to know him more.
