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From a search for gamma-ray emitting binaries in Fermi LAT data we found agamma-ray eclipsing system 4FGL J1702.7-5655 likely a redback millisecondpulsar. This type of system is rare and the eclipses are key probes of systemgeometry and the emission regions. The long-term LAT light curve shows that thegamma-ray orbital modulation changed from a simple eclipse before early 2013 toa broader more easily detected quasi-sinusoidal modulation. In addition thethe eclipse shifted to ~0.05 later in phase. From Swift XRT we identified alikely X-ray counterpart that we recently confirmed with Chandra. XMMobservations are required to provide the needed photons to investigate thedetails of the X-ray orbital modulation particularly the eclipse and much better measure the spectrum. [truncated! Please see actual data for full text]