Ended up booking F both ways, but could only get seats to NRT.
A little surprised to get an email and text message last night telling me the flights were cancelled. Turns out they weren’t so much cancelled, but rather downgraded as the aircraft is changing to three class.
Unusually, got through to someone at the executive club straight away this morning, who was pretty helpful and rebooked us into HND, F both ways.
Guess going three class is a sure sign HND is proving the more popular option.