Context: It is possible that other distinct dialect groups were already in existence during this period. Good candidates are the hypothethical ancestor languages of Alanian/Scytho-Sarmatian subgroup of Scythian in the far northwest; and the hypothetical "Old Parthian" (the Old Iranian ancestor of Parthian) in the near northwest, where original *dw > *b (paralleling the development of *ćw).

Question: What may have also been in use at the time?
Answer: other distinct dialect groups

Question: Precursors of what subset of Scythian are theorized to have existed?
Answer: Alanian/Scytho-Sarmatian

Question: What possible predecessor of Pathian is thought to have existed?
Answer: Old Parthian

Question: What was not in use at the time?
Answer: Unanswerable

Question: What is the ancestor of old Iranian?
Answer: Unanswerable

Question: c parallel the development of what other two letters?
Answer: Unanswerable

Question: Scythian was the ancestor of what other languages?
Answer: Unanswerable