Hey folks, new to the forums, but a frequent flyer.

I'm in a bit of a gray area when it comes to requiring a transit visa or not during a layover, so I thought I would check.

Here's the situation: I have a 15 hour layover in Heathrow Terminal 5. I'm on my way from a country that would normally require a visa to the US, where I have a valid visa. The layover is overnight, the first plane lands at 7:30PM, the other one departs at 11:30AM. From what I've read, Terminal 5 airside (without border control) shuts down overnight, and I am required to pass through border control for that reason.

According to the UK government's own website:

"You might be eligible for ‘transit without visa’ if:

• you arrive and depart by air
• have a confirmed onward flight that leaves on the day you arrive or before midnight on the day after you arrive
• have the right documents for your destination (eg a visa for that country)

One of the following must also apply:

• you’re travelling to (or on part of a reasonable journey to) Australia, Canada, New Zealand or the USA and have a valid visa for that country."

I believe I satisfy all four of these conditions. The bolded one is the one I'm unsure about, but I arrive Thursday evening, and my flight is Friday morning which would be "before midnight on the day after I arrive" I would assume.

If so, when I switch landside without the transit visa, does that mean I'm only through part of the checks, or would I conceivably be able to just enter the UK in the mean time? I have friends in London, and it would be ideal to have a pint and have an actual bed to sleep in before getting on the next flight.