Hi Luis,
I suspect you are using a custom field for 'Return Date' so that it does not impact native functionality.
Using the 'Date of Termination' (DOT) will remove all 'Availability' for that resource after the DOT. I would not recommend using DOT if the resource is returning.
I would recommend using your custom date to manage employees on leave if you want to know the date of return
I would look into updating their calendar to set non-working days for the time-period in which they are out. This will cause zero allocations for the time they are out and if they are added into investments, it does not impact the capacity for the planned work as this resource will not have capacity/availability during the time off.
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