Cut 3 clementines into wheels and thin wedges. Pour 6 cups of cold water into a Bundt pan and arrange clementines and thyme sprigs around the pan pushing into the water. Freeze until solid, about 6 hours.
Remove zest from remaining 1 clementine, in wide strips with a vegetable peeler, leaving white pith behind. Combine zest, tea, ginger, honey, cloves and 6 cups boiling water in a large, heat-proof bowl or pitcher. Cover and let steep 5 minutes. Strain through a fine mesh sieve, discard remains and transfer tea to a large pitcher. Let cool; stir in orange juice and whiskey and chill until cold, at least 3 hours and up to 8.
When ready to serve, dip the Bundt pan into a bowl of hot water to loosen the ice and place in a punch bowl. Pour tea and Cava into punch bowl. Serve in tea cups.