The only Iberia presence in Manchester is via their Iberia Express (I2) subsidiary, flying MAN-MAD only, from T3, and connecting from Madrid elsewhere on IB if necessary. (You can get IB codeshares on these I2 flights as well, but I2 flights post BAEC Avios and tier points normally—although there is mixed info on whether the I2 flights count as one of the required flights on BA+IB metal.)