That is outdated information from April when it was first introduced back then. It even mentions that they’re going to follow up as soon as possible which they did in their next post here:
Which at present day states:
If you encounter these restrictions on any other WoW Classic characters, you must first pay for game time and allow 26 days to pass. You can confirm your order date in your Transaction History. Game Time from WoW Tokens does not count to lift this restriction.
Recently edited 3 hours ago, which means the information is up to date.
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