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The Fermi Large Area Telescope (LAT) reported the first definitive GeVdetections of the binaries LS I +61\degree 303 and LS 5039 in the first yearafter its launch in June, 2008. These detections were unambiguous as aconsequence of the reduced positional uncertainty and the detection ofmodulated gamma-ray emission on the corresponding orbital periods. An analysisof new data from the LAT, comprising 30 months of observations, identifies achange in the gamma-ray behavior of LS I +61\degree 303. An increase in flux isdetected in March 2009 and a steady decline in the orbital flux modulation isobserved. Significant emission up to 30GeV is detected by the LAT; priordatasets led to upper limits only. Contemporaneous TeV observations no longerdetected the source, or found it -in one orbit- close to periastron, far fromthe phases at which the source previously appeared at TeV energies. Thedetailed numerical simulations and models that exist within the literature donot predict or explain many of these features now observed at GeV and TeVenergies. New ideas and models are needed to fully explain and understand thisbehavior. A detailed phase-resolved analysis of the spectral characterizationof LS I +61\degree 303 in the GeV regime ascribes a power law with anexponential cutoff spectrum along each analyzed portion of the system's orbit.The on-source exposure of LS 5039 is also substantially increased with respectto our prior publication. In this case, whereas the general gamma-rayproperties remain consistent, the increased statistics of the current datasetallows for a deeper investigation of its orbital and spectral evolution.

Long-term monitoring of the high-energy gamma-ray emission from LS I +61{\deg} 303 and LS 5039