Alternate Valuation Date rules involving stocks in large IRA

[Guest artrose]

Jones (single) died leaving a brokerage account and an IRA, about $4 mil in total. Both consisted of very large holdings of the same 3 stocks. Since his death, last month, the values have dropped substantially, and the executor is selling shares to raise $$$ to pay PA inheritance tax, and Federal Estate Tax.

The IRA is left to the same 8 beneficiaries, and each will then be the beneficiary of a Jones IRA for the benefit of......., when the custodian decides to divide the plan, and will make elections or liquidate.

The issue is how the alternate valuation date for the estate will be affected by the actions of the beneficiaries, when or whether they liquidate the stocks in their accounts, which is of course beyond the control of the executor.

The rules are clear as to how to arrive at the AVD for the brokerage account, but do any of you know how to include the IRA assets in the calculation? I will appreciate being directed to any treatises, rulings, or articles on point. Thank you very much.