Looks like Ottawan may not get the prize, given that The One is not technically at grade today.
If it becomes at grade tomorrow, it would be a tie between Ottawan and Old Boy (he guessed December 13). Whoever made the prediction earlier will be the tiebreaker.
If it becomes at grade on December 12 or 13, Old Boy would win.
If it becomes at grade on December 14, it would be a tie between Old Boy and VZ64 (he/she guessed December 15). The tiebreaker procedure is the same.
If it becomes at grade between December 15 and 17, VZ64 would win.
If it becomes at grade between December 18 and Christmas Day, Kotsy (he guessed December 20) would win.
If it becomes at grade between Boxing Day and January 2, 2020, Neilv (he guessed New Year's Eve) would win.
If it becomes at grade on January 3, 2020, it would be a tie between Neilv and Brian YYZ (he guessed January 6). The tiebreaker procedure is the same.
If it becomes at grade between January 4 and 6, Brian YYZ would win.
If it becomes at grade on January 7 or later, Irishmonk (he guessed January 7) would win.
My prediction:
Old Boy will win the subscription for a year.