Nanny - You are talking about “lactic tolerance work” - do you refer to the 4 x 200m at race pace? For a 200/400 athlete, I would definitely include Special Endurance work. Towards the end of this phase, you will have to start with Speed Endurance as well.
According to my standards, the volume per week now, is not enough to handle 400m’s in the competition season. Remember - you have to form a base NOW to be ready for the whole of the Australian season, as well as the international season.