The Piccadilly line from Heathrow to Kings Cross will be closed for route modernisation from end of day service on Friday night to end of service on Sunday on
18 to 20 July
1 to 3 August
12 to 14 September (Heathrow to Hammersmith)
26 to 28 September
1 to 3 November (Heathrow to Hammersmith/Acton Town)
21 to 23 November
Replacement bus services will run
PL1-Green Park to Osterley all stations, every 20 minutes overnight; Earls Court to Osterley all stations, every 10 minutes, daytime;
PL3-Heathrow to Earls Court calling at Hammersmith only- every 10 minutes 5am to midnight;
PL7-Hammersmith to Osterley to Heathrow Terminal 5 via Central Bus Station every 20 minutes overnight only
No buses will serve Terminal 4, PL3 and PL7 will use stand 5 at Central Bus Station, only PL7 will serve Terminal 5.
Use Heathrow Express or the Elizabeth Line or night bus H30 for inter terminal transfers.
By the way PL2 and PL4 run on the Uxbridge branch as needed, PL5 and PL6 run between Kings Cross and Cockfosters as needed.