Originally Posted by mikesaidyes

You can have two separate bookings sure IF AND ONLY IF you can get the boarding pass yourself on your phone OR the transit desk (because you cannot go out and re check in at the check in counters) AND if you have luggage it MUST be transferred by the airlines ( you can't go out and collect it and re check in)

Only possible ....within 4 hours means very simply:

If you arrive at 5 PM - your next flight out must be within 24 hours of that aka you can't stay in transit more than 24 hours....nothing to do with single booking reference at all.