Does anybody have any words of wisdom about what to expect come Jan 29 if the strike does go forth (chaos, yes, but other than than )

My 75 year old father is scheduled to return home from London -- LGW-ATL on the 29th. I told him that if he is delayed a couple of days better London than lots of places I can mention. But I do worry about him spending 18 hours a day at LGW trying to get a flight home.

He going over for a specific event (leaving Wed) and BA (according to him) won't let him cancel, only reschedule his trip (which does him no good ).

I've survived much labor action here in the US over the years, but have no idea what to expect w.r.t. the UK. Will (can?) BA try to operate? Do they have mutual support agreements with other airlines? If flights are canceled will they try to schedule him on other airlines? Just OneWorld partners? Or does he just wait until they are flying again?

Thanks in advance.