  We present an efficient analytical method to predict the maximum transit
timing variations of a circumbinary exoplanet, given some basic parameters of
the host binary. We derive an analytical model giving limits on the potential
location of transits for coplanar planets orbiting eclipsing binaries, then
test it against numerical N-body simulations of a distribution of binaries and
planets. We also show the application of the analytic model to Kepler-16b, -34b
and -35b. The resulting method is fast, efficient and is accurate to
approximately 1% in predicting limits on possible times of transits over a
three-year observing campaign. The model can easily be used to, for example,
place constraints on transit timing while performing circumbinary planet
searches on large datasets. It is adaptable to use in situations where some or
many of the planet and binary parameters are unknown.
