IOS62 was released alongside Wii Shop v21, but wasn't used by it. Instead it is used by the Wii U Transfer Tool (both on the Wii and on the Wii U).
Unlike other IOS versions, IOS62's ES sysmodule allows ES_SetUid to be called not only by the System Menu but also by the Wii U Transfer Tool. This is done by checking whether (active_title_id & ~0xff) is equal to 0001000148435300 (HCS*).
On Wii U vWii, IOS62 has a different set of exceptions. Its v6430 allows 0001000148435400 (HCT*), and its v6686 and v6942 allow 0001000148435400 (HCT*) and 0001000848435a00 (HCZ*). Note that v6942 was released as an update at the same time HCZ* was added.