Sorry, I didn't have time to reply to this thread before.
To answer the OP's question, the Iron-age Iberians were mainly descended from the Mesolithic and Neolithic inhabitants of the Iberian peninsula, who belonged to I2a, G2a, E1b1b, J1, T1a and probably also J2. But I would expect to find also a considerable amount of R1b-S116 that arrived with Bronze Age invaders who lost their IE language (like in the Basque population).
To answer the OP's question, the Iron-age Iberians were mainly descended from the Mesolithic and Neolithic inhabitants of the Iberian peninsula, who belonged to I2a, G2a, E1b1b, J1, T1a and probably also J2. But I would expect to find also a considerable amount of R1b-S116 that arrived with Bronze Age invaders who lost their IE language (like in the Basque population).