I will be arriving into Heathrow Terminal 4 at 5.50am, and my connecting domestic flight departs Heathrow Terminal 1 at 9.30am. I'm flying business class into London, so should disembark fairly quickly. I will have to collect and re-check baggage. I'm thinking it should be plenty of time, but it's a few years since I arrived into Heathrow on an early morning flight. The only fly in the ointment would be a delayed flight into London (which did happen last year, departure out of Kuala Lumpur delayed by 1 hour, but as my connecting flight was the following day it wasn't an issue). Thoughts?