From Thomas at the SWLing Post:
The frequencies that will be used for the 2015 BBC Antarctic Midwinter Broadcast on June 21 at 21:30 UTC.
and 5,905 kHz
Evidently, these were the frequencies chosen from the following that were tested:
7,425 kHz, Ascension, 207 degrees
5,985 kHz, Woofferton, 184 degrees
9,590 kHz, Woofferton, 182 degrees
5,905 kHz, Dhabayya, 203 degrees
I look forward to listening to this and reporting on it.