Wikipedia's Voting Rights Act of 1965; Amendments says:
Congress enacted major amendments to the Act in 1970, 1975, 1982, 1992, and 2006. Each amendment coincided with an impending expiration of some or all of the Act's special provisions. Originally set to expire by 1970, Congress repeatedly reauthorized the special provisions in recognition of continuing voting discrimination. Congress extended the coverage formula and special provisions tied to it, such as the Section 5 preclearance requirement, for five years in 1970, seven years in 1975, and 25 years in both 1982 and 2006.
I don't need a python program to know that 2006 + 25 is demonstrably larger than 2020, but something caught my attention in US attorney general Merrick Garland's discussion as covered in the CNN video Justice Department suing Georgia over voting restrictions after
And because the upcoming redistricting cycle may be the first since 1960 to proceed without the key preclearance provision of the voting rights act, we will publish new guidance to make clear the voting protections that apply to all jurisdictions, as they redraw their electoral maps. (my transcription)
Question: If the US congress extended the Section 5 preclearance requirement in the Voting Rights act another 25 years in 2006, why might it not apply in 2020? Why might redistricting proceed without the provision?