Thanks Simon for the idea but having looked at flights there are no AGP to LHR at anything like reasonable prices, and then i have the problem of having to get the flight into LHR to 'line up' with the flight to MNL and vice versa.

Also by making two separate bookings, with many holiday insurances, that is not possible. So if we were to arrive late at LHR and miss the connection, that would not be covered.