Now that would be really strange if you could modify the database while in recovery mode.Unfortunately you cannot test that now...
In my opinion the main question is why crash recovery took so long.The server log should be able to tell you more about it.
Is your checkpoint_timeout very high?
Was there a backup_label file in the data directory (now backup_label.old)?
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Соглашаюсь с условиями обработки персональных данных