Dear Mohammed:
Good day and thanks for asking us.
Managing project risks is a continuous process. The project manager would always reassess project risks. Risks that have not occurred will get retired. On the other hand, new risks can emerge as well. The contingency reserves will be recalculated, and as a result, they can be reduced or increased.
Please let me know if this answers your question.
Warm regards,
Khurram Hussain, PMP, CSSBB