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Multi-epoch Chandra X-ray observations of nearby massive early-type galaxiesopen up the study of an important regime of low-mass X-ray binary (LMXB)behavior -- long term variability. In a companion paper, we report on thedetection of 158 X-ray sources down to a detection/completeness limit of0.6/1.4 x 10^{37} ergs/s using five Chandra observations of NGC 4697, one ofthe nearest (11.3 Mpc), optically luminous (M_B < -20), elliptical (E6) galaxy.In this paper, we report on the variability of LMXB candidates measured ontimescales from seconds to years. At timescales of seconds to hours, we detectfive sources with significant variability. Approximately 7% of sources showvariability between any two observations, and 16+/-4% of sources do not have aconstant luminosity over all five observations. Among variable sources, weidentify eleven transient candidates, with which we estimate that if all LMXBsin NGC 4697 are long-term transients then they are on for ~ 100 yr and have a7% duty cycle. These numbers are consistent with those found for brighter LMXBsin M87 and NGC 1399, which suggests that there does not appear to be ameasurable difference between the outburst durations of long-term transientneutron star LMXBs and black hole LMXBs. We discuss in detail a transientsupersoft source, whose properties are not easily explained by standardexplanations for supersoft sources.

Measurements of Variability of Low Mass X-ray Binary Candidates in the Early-Type Galaxy NGC 4697 from Multi-Epoch Chandra X-ray Observations