SELECT date FROM table_13079788_3 WHERE gtc_winner = "Graeme Mundy Jamie Smyth" AND gt3_winner = "Hector Lester Tim Mullen"
Apa semua tanggal untuk pemenang GTC Graeme Mundy Jamie Smyth dan pemenang GT3 Hector Lester Tim Mullen
CREATE TABLE table_13079788_3 (date VARCHAR, gtc_winner VARCHAR, gt3_winner VARCHAR)