A business plan depends on assumptions that may not remain true. The buyer may delay the decision, the supplier may change terms, or the cost may rise enough that the original route no longer makes sense.
A backup plan is more useful if we know in advance when we will consider it. We need warning signs, an acceptable cost of change and an answer to the question of which goal we want to preserve. Without that, the other option can only remain a vague wish.
Changing the mode of operation does not automatically mean giving up the intention. Sometimes a different scope, deadline or market provides a more reasonable continuation. This should be decided according to the new circumstances, and not according to the pride invested in the original plan.

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