Hello Adrian#,
If I understand your setup correctly, I don't believe you'll achieve
what you want working with your current setup.
I assume when you say you "scheduled tasks from the end date" that you
set project to schedule from the finish date in Project > Project
Information. This allowed you to set your milestone date and have
project determine the start date of the project in order to meet the
milestone end date. If you add additional tasks after the "last"
milestone, those tasks will become the end date and shift your important
milestone earlier.
So, an option that *may* work (I cannot guarantee without seeing your
schedule in detail):
Go to Project > Project Information and change the scheduling option
from "Project Finish Date" to "Project Start date". This will take the
calculated start date as the start date for your project. Set a
deadline on the important milestone task equal to the current scheduled
date for the task. You can now add your "post project completion"
tasks.
I hope this helps. Let us know how you get along.
Julie
Project MVP
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