US Citizen in UK for holiday - can I reenter?

I'm new to travel

I hold a US passport. I am visiting friends in the London since December. My passport stamp says "Leave to enter for 6 months."

My friend has invited me to go from London to Hong Kong for a holiday.

When I return from Hong Kong to London, will they deny me re-entry? If so, what can I do?

I am sorry if this is in the wrong forum, I am desperate for info since she has booked the ticket and the trip is in two days.

Moving topic to General UK Immigration forum.

See also Chapter 2 - Visitors > Section 1 - Visitors (ANNEX A: GUIDANCE - GENERAL > 4. FREQUENCY AND DURATION OF VISITS).

Thanks for the help. Sorry about posting in the wrong spot

Looks like I will be ok, I'll bring my return to US ticket printout just in case.