Certain migration timestamp formats not working

It might be a bug, but seems a specification.
In short, migration only supports filenames with regex /^\d{4}[_-]?\d{2}[_-]?\d{2}[_-]?\d{6}_(\w+)$/.

See https://codeigniter4.github.io/CodeIgnit...file-names
It does not say that the migration supports filename like Y-m-d-H-i-s_.

By the way, why do you want to change the filename format like that?

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