In a small saucepan, cook the blueberries, sugar, and lemon juice over medium heat for 8 to 10 minutes until thick and saucy. Remove from heat and cool completely.

Beat the cream cheese in a large bowl until smooth, then beat in the condensed milk, vanilla, and salt until glossy.

In a separate cold bowl, whip the heavy cream to stiff peaks, about 3 to 4 minutes.

Fold the whipped cream into the cream cheese mixture gently until no white streaks remain.

Spread half the base into a 9x5-inch loaf pan. Dollop half the cooled blueberry sauce and half the crushed graham crackers on top, then swirl with a knife. Repeat with the remaining base, sauce, and crumbs. Press plastic wrap onto the surface and freeze for at least 6 hours.

Scoop into bowls and serve.