Purvapaksha- No. Singer will die at time T, where T is known to lie in the region 0 to 50 years from now. Thus, at time t < T, Singer is a person and has rights and shouldn't be eaten.
Khandana- At time T-1, Singer is a person who is going to die anyway. Eating him is the smallest sin one can incur under conditions of scarcity . Hence, it is permissible to eat him. Since it is permissible to eat him, thus killing him, at time T-1, eating him is the smallest sin one can incur at time T-2 because he only has one more instant to live, under conditions of scarcity. The same is true at T-3 and so on. Thus it is permissible to eat Peter Singer, so long as food is scarce and necessary to support the life of a person- which on Singer's view includes animals.
Siddhanta- Don't eat Peter Singer. You'll get a tummy ache. Feed him to the dogs.
Note- Under scarcity, if you eat, someone else does not- so, for Singer, a least possible sin is already occurring. Because Singer fails to distinguish between the margin and the norm, this argument, albeit only with respect to him, goes through.