My thoughts on the $10 GRD. I've done some research (perhaps I should have done it sooner) on the game. The top prize occurs about every 58,500 books (3,510,000/60). Based on public information, the top prizes were claimed as follows:
Date Book Number
1 2/7/17 (unknown book number) best guesstimate 58,500
2 3/20/17 (unknown book number) best guesstimate 117,000
3 5/13/17 (unknown book number) best guesstimate 175,500
4 6/14/17 (unknown book number) best guesstimate 234,000
5 7/31/17 257,445
6 4/12/18 412,654
7 7/18/18 459,077
The book numbers for the first four claims are guesses, but fairly reasonable given the top prize odds and the roughly 45 day period between top prize claims. Nearly every book I have seen recently is in the 484,000 range (end of print run). I saw a few in the upper 280,000 earlier this month. The very large book gap (155,214) and time gap (9 months) between the 5th and 6th top prizes claimed makes me believe that the last top prize is probably not in the upper 480s but instead somewhere in the 300s. Although not exactly scientific, this appears plausible.
Also at this time (October/November 2017), Publix started carrying the $10 Holiday ticket and may have removed books of the $10 GRD to make room for the holiday ticket. If that is the case, the top prize was probably destroyed. If not, it could be sitting in a safe in a Publix or other shop. Just my two cents. I may abandon going after this game now that I believe the top prize may not be available.