class were not scrapped, however. Instead, they were retained by the expedient of reclassifying them as training ships. As a first step, Frobisher was reclassified in 1932, and one of her aft guns and two of her 4-inch guns were removed; in 1935, the upper aft gun was replaced by an aircraft catapult, and in 1936, to conform more closely with the agreement, her armament was reduced to a single 4.7-inch (120 mm) gun. In 1937, Vindictive was specially demilitarised with a more substantial conversion; not only was her armament reduced to two 4.7-inch guns forward and a pom-pom aft, but her inboard propellers and the associated turbines were removed, along with the associated boilers and aft funnel, reducing her speed to 24 knots. A reworked superstructure provided cadet accommodation, while the empty aft boiler room was became a laundry, and her fuel reserve dropped to . Hawkins was simply disarmed and laid up. However, in 1937 Effingham began substantial reconstruction, which saw her converted into a light cruiser, albeit of a more old-fashioned configuration with nine BL 6-inch Mark XII guns on single mountings CP Mark XIV. This was achieved by rebuilding the superstructure to increase the number of superfiring positions fore and aft from two to three, designated 'A', 'B' and 'C' and 'W', 'X' and 'Y' respectively, while retaining the guns on either wing, and the one right astern on the quarterdeck in position 'Z'. Secondary armament became eight QF 4-inch Mark XVI gun in four twin-gun HA/LA Mark XIX in mounting, eight QF 2-pounder Mark VIII guns in two quadruple mounts and twelve Vickers in three quadruple mounts. The submerged torpedo tubes and the after boiler rooms were removed, but they were replaced with extra fuel storage, and after modifications to her remaining machinery, her total output was only slightly reduced to . Externally, the remaining uptakes were trunked into a single large funnel. She had a new bridge, her original tripod mast and spotting top were replaced by a straight pole mast, and carried a crane amidships designed for a reconnaissance aircraft, although it is not clear if the associated catapult was ever been fitted, and probably no aircraft was ever carried. In 1939, Vindictive entered dock for what was supposed to be a reconstruction into a similar configuration, but work proceeded slowly, and given the extensive modifications to her machinery, it was decided to