Here’s the chart of total supply increase per epoch, so let’s use 0.45% (this may be a little on the low side as more stake unlocks and/or fill rate changes, but it’s going to be ballpark correct).
So extrapolating that out to 15 months (or 30 epochs) I get the following chart for supercharged yields for your values (assuming the hard fork is at epoch 20 slot 142800 and the second drop off starts at the start of epoch 24 for simplicity, which is slot 171360)
