Combine graham cracker crumbs, sugar, cinnamon, and butter in a bowl. Press onto the bottom of an ungreased 9-inch springform pan. Refrigerate for 30 minutes.
Preheat oven to 300 degrees F (150 degrees C).
Place strawberries and cornstarch into a blender. Cover and puree until smooth. Pour strawberry sauce into a saucepan.
Bring to a boil over high heat. Boil and stir until sauce is thick and shiny, about 2 minutes. Set aside 1/3 cup strawberry sauce; cool. Cover and refrigerate remaining sauce for serving.
Beat cream cheese in a mixing bowl with an electric mixer until light and fluffy; gradually beat in condensed milk. Mix in lemon juice and vanilla extract, then beat in eggs on low speed until just combined. Pour half of cream cheese mixture over crust; drop half of reserved strawberry sauce by 1/2 teaspoonfuls on cream cheese layer. Carefully spoon remaining cream cheese mixture over sauce; drop remaining strawberry sauce by 1/2 teaspoonfuls on top. Cut through top layer only with a knife to swirl strawberry sauce.
Bake in preheated oven until center is almost set, 45 to 50 minutes. Cool on a wire rack for 10 minutes. Carefully run a knife around edge of pan to loosen; cool 1 hour longer. Refrigerate overnight. Serve reserved strawberry sauce with cheesecake. If the sauce it too thick, stir in water.
