Health insurance for 19 year old not in full time education?

My daughter has withdrawn from college for a semester for health reasons. HR department at my work says that she is not covered under my health insurance because she is not in full time education......but that under the health care reform bill we can add her back on our plan when we get the re-enrollment details in June. If she is already on the plan can they remove her given that this particular part of the reform bill started in Sept 2010.