Often, individual player prop numbers are set in advance of the game that will be played on the same day.
The line and point spread in the NBA game can move sometimes several points throughout the day as tipoff approaches.
Frequently, the NBA player prop bets on those games are sometimes not changed immediately to reflect subtle changes in the overall point spread or total.
This shouldn’t be regarded as an angle shot by the customer since the actual line of the given prop is likely negligible. In fact, you only may be taking advantage of paying less vigorish on your specific prop.
Still, if a game total is moving down and there were props that you were interested in going UNDER on, you may have a bit of an edge on the line in a correlated way.
Is would make sense that is a game total or a particular point spread is headed in a particular direction, then the statistical output for the players in the game would likely be affected.
Because books are more focused on high-volume markets such as spreads and totals, these props may often not be adjusted until a decent amount of action comes in on the likely value side.