ALCON:
The "restricted" ATP is a relatively new creation, as a result of the 1500 hour rule that went into effect on 1 Aug of this year. As a result of a law passed after the Colgan Air crash, Congress mandated that ALL pilots flying in Part 121 operations had to hold an ATP, even FO's. Previously, an FO could operate on a Commercial ticket. However, as a result of ALPA efforts, a "restricted" ATP was created by the FAA to allow pilots who received training from either 1) an accredited 4-year aviation university (example: UND), or 2) the military, to obtain a "restricted" ATP with less than the full 1500 hour requirement.
The stipulation being put out is that, for the purposes of being accepted as an applicant to United, you have to have an unrestricted ATP...i.e., not a "restricted" one. I would imagine that all the Majors will put this word out in the near future...the only place I can see accepting "restricted" ATP holders will be the Regionals.
If you have an ATP, and you don't already know that you have a "restricted" one, I'm pretty confident yours is the "unrestricted" variety, and hence, you have nothing to worry about. The VMC circling limitation is not it...I have an unrestricted ATP with that limitation on it.
Also, this answers the question why the past minimum of a Commercial ticket is no longer acceptable.
For the armchair FAA lawyers out there, I'm sure there is some minor detail or two in this explanation that I've left out...my purpose was not to quote chapter and verse, but to answer the general question being posed on this forum.
Now, we could talk about whether the 1500 hour rule was an appropriate answer to the event that precipitated it, but that's a whole different discussion...