Good advice, guys. Thanks
Here's the plan then.
1. Buy the new Zwift Hub for Christmas! This will get me training immediately. I'm a bit of a fair-weather cyclist and don't enjoy riding in the rain or on icy roads (ironically the exact weather today).
2. Mix in some climbing races with standard Zwift training plans
3. Adjust diet to less sugar and carbs to fats, protein and green veggies. Cut down alcohol from 25 units a week to 10 (need to be realistic here)
4. Outcome of the above is to drop from 92kg to 85kg (I'm 6'4" so not starting from a position of easy weight loss)
5. Focus on hill reps as part of outdoor riding, in addition to standard 100km rides, once weather improves, likely March to July.