iyahamon: the labor code in my opinion does not expressly provides that an employer shall furnish notice or advice about impending policy changes on rules and regulations. This is so because changes in policy on rules and regulations are "management prerogative". However, management prerogative should not be abused to the detriment of employees, hence, for sound employer and employee relationship and for fairness as well, management through the HR, is impliedly obligated to keep employees well informed about changes on any rules and regulations affecting their relationship, otherwise, should any situation/circumstances arises that would compromise the employment of the employee, due to the absence or failure to give due notice, a case for illegal dismissal or unfair labor practice is not a remote possibility.
Hope answered your query.
Atty Karl Rove