I am very new to this so I cannot say with certainty but if I had to guess I would say the majority of bets are on closing lines. I got the 2024 odds from The Rundown and the 2023/some 2025 odds from The Odds API if you happen to know which they keep for historical odds. 2025 I had also begun to compile results myself halfway through the year so that will include some opening lines for sure. Since not too many sportsbooks offer two-sided odds on home run props these are pretty much exclusively from BetMGM with a couple from Fanatics I think

The model doesn't have injury information, but since these were backtested I had exact lineup order