185 Lbs of Ballast,
My other half is cabin crew and I work shifts. We found ourselves in exactly the same situation as you a few years back. However we found a fantastic 24/7 nursery that caters for 6months-4years kids. It is a highly professional firm, only employing trained and registered childrens nannies giving complete peace of mind. From experience it seems to be mainly airport/airline staff that use the facility and as a result the staff are familiar with, and understand the disruptive and irregular/anti-social hours style of work we do.
Unfortunately, as far as I am aware, the nursery group concerned don't yet operate in your LTN area but I gather that they do have expansion plans and if nothing else it may be worth giving them a call and see if they opening up in your area. If not they may be able to point you in the direction of a similar facility around LTN. PM me if you would like the contact number. Hope this helps.