Does anyone know what the "held" seats mean? I have tried even booking a space positive ticket but United says there are no seats left. Can it be a weight restricted flight? Flights within the next few days show 0 held seats but all flights further out show 6 held seats. Thanks for your help!

XXX-XXX Avail. Capacity Auth. Booked RSB Held PS SA Group
F/C/Y: 0/0/-1 16/0/144 16/0/145 16/0/139 0/0/0 0/0/6 0/0/0 0/0/1 0/0/0
Totals: -1 160 161 155 0 6 0 1 0