I was also thinking that, but the way it was worded, "Gibbons says Jays have "pretty good idea" who will be dropped to make room for Reyes" makes you think a DFA/Option is in place.
I also asked Ben-Nicholson Smith this question and he gave me a smart answer, "If the Jays thought that Melky needed a DL stint, they wouldn't have waited until Reyes to get activated"