I'm wondering if it levels out actual reserves through the month to keep weekends from dropping down to min as much (or simply raising the min if there is a "surplus" of reserves available for a given month). If that's the case that would be an earth shattering concession that would dramatically reduce GS assignments as well as abrogating the seniority of reserves and severely restrict schedule moves.

I'm hoping that's not what this is, but it fits the theme of deep concessions that reduce pilot staffing in exchange for modest pay rate increases.