If your first 9 layers are consistently named between your original trained model and the new model, then you can use model.load_weights() with by_name=True. This will update weights only in the layers of your new model that have an identically named layer found in the original trained model.
The name of the layer can be specified with the name keyword, for example:
model.add(Dense(8, activation='relu',name="dens_1"))