Newy,
extremely long fasts such as this are not recommended unless under qualified supervision. Anything beyond 40 days (or even before that) can result in electrolyte deficiencies, and esp' so in potassium.
Fat reserves, although essential on a fast, are not the only food-reserves that need to be taken into account, and where Shelton and others would stress the safety of a fast, and how long one can do so, are entirely dependent on the pre-fast diet and its quality.
I am also dubious about this being a water-only fast, because of the energy-levels of the faster being so high at this stage of her fast.