Honestly, this is really good to hear! More mainstream accounts will definitely get the fediverse a bit more credibility.
And here's a bit more from BBC:
The team at BBC Research & Development are researching social technologies and exploring possibilities for the BBC. One part of our work is to establish a BBC presence in the Fediverse.
This is an experiment - we will run it for 6 months, and then look at how much value it has provided, how much work it requires to maintain and then decide whether and how to continue. We're learning as we go, and we'll write about what we discover in the hope that it might be useful for others. The BBC will continue its normal social media activity in the usual places.
We're starting off small with just a handful of accounts from R&D and our colleagues at BBC Radio, but we hope to be adding more accounts from other areas of the BBC soon:
brainfreeze