Hi I would like to ask about the newborn recommendations with sleeping bags. Will they startle themselves leading to more harm then good with having the arm holes or is it a safer option with the sleeping bag over a muslin wrap? I will be having my first baby and will be a winter baby as well so have brought a newborn warmer nights sleeping bag from bonds

Red Nose recommendation for a sleeping bag includes the following
“A safe baby sleeping bag is constructed in such a way that the baby cannot slip inside the bag and become completely covered.
The sleeping bag should be the correct size for the baby with a fitted neck, armholes (or sleeves) and no hood.”

These can be used from birth, but ensure the bag is not too large (especially round the neck)  for baby.  https://rednose.org.au/article/what-is-a-safe-sleeping-bag

Red Nose recommends using a light cotton or muslin wrap, but not in conjunction with a sleeping bag.
https://rednose.org.au/article/safe-wrapping-or-swaddling-when-to-stop-and-how-to-select-a-safe-sleep-bag