It's important to realize that doing this to a direct report, while less painful than immediate termination, represents a traumatic shift in the terms of employment. Very few employees will be able to function on such a dramatic cut in their earned income. A handful, who are devoted to their job for one reason or another, will look to supplement this now part‐time job with another part‐time stream of income. Most will simply start looking for another full‐time job, using the free time they now have to do their job hunting. Some may actually request termination instead, in order to search for a new job full‐time. In that case you should provide them with the same severance package they'd receive if you were terminating them. Even though the odds are high that you'll eventually lose your current employee, it's worth making the effort to keep them in place for as long as possible, rather than just firing and then rehiring a new part‐timer. You have someone who knows the job and, presumably, is good at it. Hiring someone new involves a cost and a risk you may as well defer for as long as possible. Try to give at least one month's notice before the change takes place. That gives the employee a chance to make whatever personal arrangements they can to compensate for the cut in income. It is likely they'll also use this time to look for another job. That's only fair.
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