This has been an interesting question I posed - I think maybe it should be on the debate forum
with all the differing views.
I've obviously moved on from here as I posed this when L was not 9months and is now 10.5months. For those interested, I went with the cows milk. My research and advise in my country is ok for cows milk to be added to things from around 9months just not as a substitute for a bf/ff meal 'til 12months.
Just for the record, she doesn't seem to really like custard anyway...prefers yoghurt
thanks