some agencies/stat boards are quite flexible in promoting and rewarding long service staff. Some people get promoted to fake/nominal titles like 'Senior' Assistant Director. These people are drawing MX9 pay because they've reached the required amount of years put in but a DD post isn't vacated or available yet. I've personally seen some cases in my own office and yes i've actually seen their pay grade in the orbat chart (which was accidentally attached in an email sent to me). They do indeed draw mx9.

Now, have you ever seen a 'fake/nominal HOD' around? Statistically speaking its just works against you. There are only so many HOD posts in one school, with 70,80 teachers all clamouring for that few positions. In ministries and stat boards AD/SAD/DD's are dime and a dozen.