Yes, guilty as charged. Ong does this in the reading and it has caused confusion so I *meant* to be careful about not replicating the confusion.
Generally in Ong, as the *drawn portion* of the commitment (COM) becomes outstanding (OS), we are generally referring to the unused (or remaining) commitment.
e.g., V = 0S + COM should really be: V = OS + unused COM
and
AE = OS + alpha * COM would be better if:
AE = OS + alpha * unused COM