Booked to travel from Manchester with BA then onto Perth via Hong Kong with Cathay Pacific. We land at Heathrow at 4.30pm in terminal 5 and have to get to terminal 3 for connection leaving 6.20. It has all been booked as one ticket via agengy not as 2 separate flights. Anyone done this, will it be enough time?. Will insurance cover us if we are late landing at Heathrow?