Yep, I got this too, but I believe them when they said they'd send me a new one. All my recent BA transactions have gone on my Amex Gold though, so I don't think this is related to the BA breach (unless Lloyds is being hugely over-cautious).

Could be related to that Lloyds/Amex data leak about a year ago, when lots of cards were blocked for fraud, even when the cards had been locked in people's drawers. Maybe Lloyds has finally realised what happened...