These second notices went out as a result of value changes after the initial revaluation notice. The second value could be for a number of reasons, primarily new construction that was completed after the initial notices were sent. If an owner received a subsequent notice they can appeal the second notice.
The appeal deadline for filing appeals on the initial notice of value was March 14. This small group of second notices went out on Monday, March 21 along with notices for commercial property and condominiums. Deadline for filing an appeal for those three groups is April 19.
CharMeck 311 is taking calls and answering questions about revaluation. Additional information can be found at http://reval.charmeck.org