@NCperson
I have read the examples in Pub939 and concluded that conceptually the General Rule is a very simple straight line amortization of basis in the contract, until the basis allocation is depleted. I cannot detect anything with respect to my case which would direct me to deviate from that approach.
The publication also describes how I should address the deviation from the 1099-R:
"If you choose to refigure your tax-free amount, you must file a statement with your income tax return stating
that you are refiguring the tax-free amount in accordance with the rules of Regulations section 1.72-4(d)(3)" I would imagine that TurboTax will generate this kind of statement, given that there is a question in the screen flow to allow self-determination of the taxable amount.
I have given some details about my annuity payments in another post to this discussion today. I hope those will be sufficient for you to understand my concerns.
