QueueControlFlags

The byte at offset 0x01 in a DISPATCHER_HEADER whose Type is QueueObject (0x04) was the single member Abandoned, starting with Windows Vista, until Windows 8.1 broke it into bit fields:

Mask Definition Versions
0x01
UCHAR Abandoned : 1;
6.3 and higher
0x02
UCHAR DisableIncrement : 1;
6.3 and higher
 
UCHAR QueueReservedControlFlags : 6;
10.0 and higher