King Charles is set to appear on Sir Elton John’s Apple Music radio programme, “Rocket Hour,” sharing musical memories and favourite artists. Multiple outlets say the recording is done privately ahead of broadcast, with the show featuring discussions between the King and the singer.

According to The Independent and other reports, the pair recorded the episode “in secret” at Apple Music Studios in Battersea Power Station. The Mirror adds that the King reflects on favourite music performances during his appearance and that the shared artists have been bolstered by the King’s Trust.

The outlets also differ on the emphasis of timing. The Evening Standard says the programme airs on Charles’s 78th birthday on Saturday, while other coverage focuses more on the behind-the-scenes nature of the recording and the format (radio show or podcast framing) rather than the exact air date.