Just a warning here for anyone who may get scammed:

While I was trying to get hold of BAH today because of the LGW incident, against my advice my OH insisted on tweeting @British_Airways and #BritishAirwaysHolidays to get a response.
She then received three 'responses' from accounts purporting to be British Airways, British Airways Head of Customer Success and Sean Doyle@British Airways manager. None of these three accounts have more than a handful of followers but she did give her phone number and the PNR out via DM.

She then received a phone call from what we now suspect was an African number, trying to help us. All this while I am on hold to BAH. At this stage I was not aware of the scam and was trying to get her to hang up as I didn't want CS to muddy the waters, knowing how efficient BAH can be.

Thankfully she finally gave up after smelling a rat and refusing to hand over any further personal info.

We don't think they have our surname and MMB seems untouched at this stage. Our account is OK as the password is going to be pretty tough to crack, but it does worry me when I realise just how much info is available on MMB if they did have the surname and the PNR.

I personally hate Twitter and refuse to engage. I think I may have finally convinced OH to stop using it. It's the wild west. I hope this tale may be a help to others.