In [1] a new integer-estimable GLONASS FDMA model was introduced. The new model is generally applicable and guarantees, independent of the actual channel number entries, the integer-estimability of the new GLONASS ambiguities. As the model has a close resemblance with CDMA models, available CDMA software is easily modified and existing methods of integer ambiguity resolution can be directly applied. In this contribution we will show how the integer-estimable FDMA model can be combined with the new GLONASS CDMA signals that are currently under development [2, 3]. We present the combined GLONASS-only FDMA+CDMA model and we analyse its strength for instantaneous integer ambiguity resolution. This will be done formally as well as empirically using real data.