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If the derog has been removed and all other things remain equal, then your score should be recovered instantly upon the correction of the late.
Did you pull myfico report after the correction updated to you CR? Sometimes it can take time from the point the CU instructs CRA to correct and the time the CRA actually updates the TL in your CR.
Verify that your CR shows all corrected info, then pull FICO from this site. Your score should be back.