X. Jerico, the project owner, entered into a Construction Contract with Ivan for the latter to construct his house. Jojo executed a Surety undertaking to guarantee the performance of the work by Ivan. Jerico and Ivan later entered into a Memorandum of Agreement (MOA) revising the work schedule of Ivan and the subcontractors. The MOA stated that all the stipulations of the original contract not in conflict with said agreement shall remain valid and legally effective. Jojo filed a suit to declare him relieved of his undertaking as a result of the MOA because of the change in the work schedule. Jerico claims there is no novation of the Construction Contract. Decide the case and explain. (5%)