How do I delete the info in the duration, start and finish cells of specific tasks only?

I want to show the empty cells as under procurement ets. I want to delete all Planning phases duration and dates to show empty cell?

​How do I delete the info in the duration, start and finish cells of specific tasks only?I want to show the empty cells as under procurement ets. I want to delete all Planning phases duration and dates to show empty cell?   Read More

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