"Approval" does not mean "confirmable".
Most people think this relates to the solicitation process alone. Plans may also have components that are defective legally.
Even if a plan is confirmed, it can be modified post-confirmation as long as nothing materially has changed. For example, STBPQ has a confirmed plan but the investor, Merrill Lynch, walked away due to the financial meltdown. However, any proponent be substituted for Merill Lynch if they have funding.
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