Thank you Bill.
I was intrigued by the low value of the capacitor value across T11. So that makes more sense.
I find interesting the size of the output transformer on the PennyWhistle compared to the BN43-202. It might explain the warm temperature of the T11 transformer at 18-15 Watts. I will try a BN43-3312 as it should still fit in the space between the finals.
I will definitely try your suggestions.
All the best,
73, John (VK2ETA)