First wanted to say thanks for the various explorer topics in this forum they were a fantastic resource.

My Q is before I ring up BA can I change my remaining 2 legs from LHR-DOH-ARN to LHR-DOH-LHR when I consider my previous routing ARN-LHR-HKG-KUL-HND-SFO//YVR-JFK-MIA-JFK-LHR

I'm not sure if I can visit London one more time or if I can have a different start and end point.

Any help greatly appreciated.