In a medium bowl, add 1 cup sliced strawberries, 1 cup mixed berries, 1 tablespoon sugar and the juice of 1/2 a lemon. Gently mix all ingredients and set aside to macerate 30 minutes.
In a food processor, puree 1 cup of mixed berries until smooth. Set aside. Refrigerate the remaining 2 cups of the berries to use as the topping for the cake.
In the bowl of a stand-up mixer, beat on medium speed the cream cheese, powdered sugar, vanilla, all the lemon zest, and the juice of 1 lemon about 4 minutes or until the mixture is light and fluffy. Add the heavy cream to the mixture and continue to beat until it forms stiff peaks, about 1-2 minutes. Remove only half the cream mixture to a medium bowl and add the berry puree and the macerated fruit (not including any juices that have accumulated). Fold mixture until it's well combined. The other half of the whipped cream mixture remains plain.
Line a 9X5 inch baking dish with plastic wrap, allowing it to overhang on all sides. Transfer 1 cup of the plain whipped cream mixture to loaf pan and spread evenly on the bottom. Put the rest of the plain whipped cream mixture in the fridge.
Place a single layer of the cookies in the loaf pan on top of the whipped cream mixture. Don't worry about any small gaps, you can break up a few cookies and add small pieces to any significant gaps. Spread a half cup of the berry whipped cream mixture over the cookie layer.
Repeat with another single layer of cookies, the second half of the berry whipped cream mixture, then a third single layer of the cookies. Cover the top with plastic wrap and refrigerate a minimum of 6 hours or preferably, overnight.
Remove the top layer of plastic wrap and invert it onto a rectangular platter. Peel the rest of the plastic wrap off and spread the remaining plain whipped cream mixture over the top and sides of the cake. Decoratively arrange the remaining berries.