So the BBC article says this:
The BICEP team’s strategy was to target the cleanest part of the sky, over Antarctica, and it used every piece of dust information it could source to do the disentanglement.
But apparently, the original assertions were based on a PDF scan of the Planck dust data!
Now we see:
There is “significantly” more dust in BICEP’s “southern hole” than anticipated. Indeed, most of the American signal – perhaps all of it – could have been attributed to dust.