Help - 1st contract - being held to ransom

[Wanderer]

While true, is it not usually the case they have the same clause in their contract with the end client?

Yes. I have never heard of a contractor paying an agency off it has always been the agency doing a deal with the client to release the contractor from their restraint of trade.

Most of this is just bluster though, I'd be inclined to call their bluff on it.