In the late 1960s all four of the batch-1 County-class vessels were planned to be upgraded with the superior Sea Slug Mk-2 system, but the upgrades were cancelled in 1967–68 because the amount of time the ships would be out of the operational fleet while being refitted. However, some batch-2 improvements were made during mid life refits, including upgrading the Seacat system from GWS21 to GWS22 and fitting Type 992Q target indicator radar instead of Type 992. "Kent" was refitted from June 1969 to December 1972.