@anomnomnomaly no, they block access from commercial VPN endpoints in known netblocks. Run your own VPN and you're fine.
My point, though is that they don't "block *anyone* from using a VPN", they're selective.
And they block so that people who can't pay for a license fee and/or are in a territory where they sell their content commercially, can't freeload off iPlayer. They're protecting *your* investment as a license fee payer.
You should use broadcast TV or radio; they can't track that