Bulletin from the UK Government that is listed as current today 10 April 2020, last updated 7 April, advises in part:
"If you live in the UK and are currently travelling in the USA, you are strongly advised to return to the UK now.
"There remain commercial options to return to the UK from the USA. If you live in the UK and are currently visiting the USA you’re strongly advised to return now by commercial means. Don’t run the risk of getting stranded."
"British Airways (BA), long-haul services are due to be suspended from San Francisco imminently. If you have a flight booked on this service, you should contact BA about your booking.
"If you wish to return to the UK, the following airports are operating transatlantic flights:
JFK (New York)
LAX (Los Angeles)
BOS (Boston)
IAD (Washington DC)
SFO (San Francisco)
ORD (Chicago)
SEA (Seattle)
MIA (Miami)
EWR (Newark)
ATL (Atlanta)
'If you are looking for a flight, check the relevant airline websites:
American
British Airways
Delta
United
Virgin Atlantic
'If there are no longer direct flights available to the UK from your current location, use airline websites to book connecting flights to cities where flights are available to the UK.
'You should now:
-contact your airline, travel company or transport provider as soon as possible to book your travel
-contact your insurance company, if you have travel insurance
-sign-up to email alerts for this travel advice to be notified if the situation changes
-check our social media accounts for where you are.
-be prepared that your plans may need to change at short notice
-See additional advice on making travel plans to return to the UK, or what to do if you cannot depart immediately.
"Transit through the US
UK citizens are still able to transit the USA on an ESTA visa waiver but only if they have not been in the UK, Ireland, Schengen zone, Iran or China within the previous 14 days. For further information please consult advice from US Customs and Border Protection.
"If you’re in transit, you’re encouraged to have evidence of outward travel to meet the 14 day requirement to hand (boarding passes, travel itineraries), build in extra time to get through airports and check the website for local CBP contacts.