QWERTY9
When I worked at Gatwick the taxi times were the same for both runways at 20 mins in the summer and reducing to 15 mins in the winter period. Therefore in your example the earliest slot available for a 1200 EOBT (should a slot be required) would be 1220 in the summer and 1215 in the winter. Giving ealiest time for departure of 1215 in the summer and 1210 in the winter.
