How to report partial cash liquidation distributions after stock basis reaches 0, and final distribution is not in a given tax year (a past year or future year)?

I received a partial cash liquidation last year that reduced my stock basis to 0, plus a sizable excess.  That distribution was reported on my brokers 1099-DIV form.
 This year I received another partial distribution, and it does not show on any 1099 forms from my broker.  The stock is held in escrow and not traded, and will be discontinued when the final distribution is made.

IS my understanding correct that this kind of cash distribution does NOT have to be reported (and taxed!) this year, as long as the stock still has a pending final distribution to be made, even though that doesn't occur until a following year?

If so, that means the excess when the stock basis reached 0 that I reported (and paid tax!) last year was incorrect, and should have been recorded and included as part of the total taxable proceeds after the final distribution and dissolving of the underlying stock shares.  Can (should?) I file an amended return for last year to get back the tax I erroneously paid?  Do I have a choice, assuming I can decide based on my estimation of my tax rate last year versus a coming year?