Do you know the bus number of the night bus that runs along Bath Road & goes to Heathrow? This is the strip of airport hotels (Ibis et al). We need to identify a bus that will be running around 4:30 am. (Not the Hoppa bus, the free city bus)
Actually, yes, the city bus that runs between Heathrow and the Bath Road hotels is a free bus. We have taken it several tiimes but in the daytime hours. I don't recall the bus number. My assumption is that a bus at 4:30 am would be a different bus and schedule. I'll look again at your link ... I had been there but couldn't identify the specific bus.
Here's a link to info. on the free local bus alternative to Hoppa:
It looks like the regular local bus runs early enough -- no need for a night bus after all. Weekdays the first bus arrives at Terminal 5 just before 4am. It's bus 423 and here's a link to its schedule: