Let's look at CPA-08502 from a timeline perspective:
Sept 30 Y2 - Payment Made
Dec 31 Y2 - Financial statement date (3 months after the payment)
Sept 30 Y3 - Next payment to be made
Our balance sheet is as of 12/31/Y2. As of that date, we will accrue the three months of interest that we owe on the note ($7500), because as of that date, we owe it, and we will pay it within the next year. We will also classify the 300,000 that we will pay in Y3 as a current liability.
What we cannot do is classify any of the interest that is NOT owed on 12/31/Y2 as a current liability on the financial statement date. What happens if we decide to pay the loan off on Jan 1, Y3? There will be no further interest due so if we accrue future interest owed, the financial statements are misleading.
The balance sheet is as of a certain date. We only report what is owed on that date. We owe 300,000 in current liabilities, 300,000 in long-term liabilities and $7500 in interest on December 31, Y2.