Removal of director can be done by passing a resolution for the removal of director or directors as the case may be.
While you are removing the directors there must be at least two directors left or the approval may not be granted
Also you can add other directors while removing some.
This should not take more than a week, however the Corporate Affairs Commission takes longer period in approving post incorporation matters some times, and this can be beyond the control of the lawyer.
Hope this helps.