Based on my information from ETrade and a broker here in my office, the portion of the A/S that will be included in the R/S is the portion that is in the O/S - Now maybe that is not how it happens, but the understanding is that that is how it is supposed to happen.
Example: 6,500,000,000 Authorized Shares
3,500,000,000 Outstanding
100:1 split
3,535,000,000 Authorized Shares
35,000,000 Outstanding
Only an example, and like I said, I was told by Etrade and another broker here, that that is how it is supposed to happen, not that it always does.