Join Date: Aug 2011
Location: Barcelona, London, on a plane
Programs: IB+ Gold, TK E+, Hyatt Globalist, Marriott LTP, IHG Diamond
Posts: 14,182
If you are booked on "three tickets" you can take whatever flight you prefer.
If you are booking a single TLV-LHR-JFK ticket you can have <24 hours in London, including overnight, and still avoid UK APD tax.
Whether DL Skypesos lets you do that is a question for the DL forum.