Your questions really revolve around corporate debts and a failing s corporation. Bankrupting personally seems like it's your choice, but you didn't address why this is needed. You also seem to think that you are personally liable for many of these debts. Please confirm that.
Changing from cash to accrual basis for the s corp really doesn't do much for you in bankruptcy. Sorry that the previous question and answer didn't address this at all.
Your s corp passes through losses to you up to your basis and at-risk limitations in the s corp. If your s corp has run up significant losses, it's likely that you have used up your basis (and at-risk limitations), and additional losses would not be usable. Your focus on creating accrual basis losses that you admit are not legit (the debts accrued will not have to be repaid) is misguided.
In personal bankruptcy, you will be allowed to keep certain exempt property, and your personal debts in excess of assets extinguished (except for those not eligible for relief, like trust fund recovery penalties, etc.). Tax
losses you create by switching to accrual may not survive the petition. Hard to say without a full review of all the facts.
You also seem to think that you are personally liable for the debts of the S corp. Again, unlikely, and certainly premature without a review of the arrangements. Also, any guarantees you are liable for may have tax consequence, as they likely do not generate at risk or basis.
A review of these rules
and your specific facts are imperative before you file. It is possible, for example, to just dissolve the S corp if you aren't personally liable for the debts. There are a number of issues to review with a bankruptcy attorney before looking at the tax side of things.
In personal bankruptcy, the tax attributes you might generate, like a usable S corp loss, are reduced by application against debt forgiveness income. Generating a larger S corp loss by 'going accrual' is meaningless when you lose the benefit against the debt forgiveness income.
There's a lot to this subject, but my take on it is that you were focused on creating a tax loss without determining if you could use it or even if your personal bankruptcy was appropriate. applying for a change of accounting method via Form 3115 is a lengthy, challenging application, and likely worthless to you. That's why I responded, and reviewed your question.
A tax professional in your area, one with bankruptcy experience, and a bankruptcy attorney will be invaluable. Do not try to do this yourself, or even with the input of Just Answer CPA's.
I'm PDtax. Ask any follow up you like, or leave positive feedback to close out your question.