We present a Monte-Carlo study of the phenomenology of Cherenkov light wavefronts fromlow energy gamma ray induced air showers. Experimentally the measurements of the spatiallydistributed arrival times of the wavefronts of the Cherenkov light of gamma ray air showers havebeen used to extract the directions of the showers. This has mainly been done for > 500 GeVshowers using a conical fit to the timing structure of the wavefront. This directionality is then usedto contribute to the rejection of background showers (mainly hadron induced showers) which arriveisotropically. Investigation of the arrival times of simulated Cherenkov photons from gamma rayinduced air showers of energies 100 GeV and below reveals that there is greater variation in themorphology of the wavefronts than at the higher energies and that the fitting of simple conicalfunctions to determine arrival directions may no longer be appropriate. We present alternativemethods of reconstructing shower direction for these low energy showers. We show examples of lowenergy showers with unusual wavefronts and discuss the properties of the cascades which result inthese wavefronts. We demonstrate that the detailed structure of the wavefront of these low energygamma ray showers is primarily determined by the height distribution of the emitting cascadeparticles. Preliminary work suggests a correlation between the shape of the wavefront and the heightof shower-maximum. We address the implications of these results on the design of systems to detectgamma ray air showers in the sub-100 GeV regime.