TTotten@nyiso.com writes to the NYISO_TECH_EXCHANGE Discussion List:

The NYISO is reserving hours beginning 05:00, 10:00, 13:00, 19:00 - 20:00, and
22:00 - 23:00 in the April
17, 2001 Real-Time Market as well as the following hours per ECA20001006B to
verify prices:

PJM:  03:00-04:00
NE:   01:00-06:00
HQ:   01:00, 03:00-04:00, 15:00
OH:   03:00-04:00
The prices for the April 18, 2001 Day-Ahead Market are correct.