For the Bundt ice ring: Pour 1 inch of water into the bottom of a 12-cup Bundt pan. Add a quarter of the cranberries, 5 thyme sprigs and 2 bay leaves and evenly spread the ingredients around the Bundt pan--this will be the top of the ice cube. Place in the freezer to set for at least 4 hours.
For the next layer, add enough water to fill halfway up the Bundt pan, then add the same quantity of ingredients as the first layer. Place in freezer for at least 4 more hours. Continue to make 2 more layers and freeze in the same manner, freezing each layer at least 4 hours before adding on the next. The final layer should freeze 8 hours or up to overnight before being used.
Turn the Bundt pan onto a baking sheet and hold under running hot water until the Bundt ice ring releases onto the baking sheet, 5 to 10 seconds. Add to a punch bowl when ready to serve.
For the spiced-thyme simple syrup: Combine the sugar with 2 cups water in a saucepan. Bring to a boil and cook until the sugar is dissolved. Remove from the heat and add the allspice, cloves, thyme and cinnamon sticks. Let steep while it comes to room temperature, 1 hour. Strain and refrigerate until ready to use.
For the punch: Stir together the cranberry juice, vodka and 2 cups spiced-thyme simple syrup (save the remainder for another use). Pour over the Bundt ice ring in the punch bowl and top with prosecco and cranberries for garnish. Serve immediately.