Knowing which month breaks is half of it. The other half is finding out, in ninety seconds, which of the three things you could do about it actually helps.
Each figure is that change applied to the whole model — the burn, the drawdowns, every milestone that depended on it, and the range. Not the one number you thought to check.
The live plan does not move until you apply one.
Against a live plan of 5.6 months
| Delay two hires to Q3 | +1.4 mo |
| Extend period 2 by six months | +0.9 mo |
| Bridge $200k in December | +2.1 mo |
| Series A slips to June | −1.9 mo |
| Lose the largest customer | −3.4 mo |
Keep one, discard it, or hand it to somebody.
The reason everybody has plan-v3-FINAL-actually.xlsx is not disorganisation. A spreadsheet has no way to hold two versions of the truth at once, so you make a second file — and from that moment you have two models and no way to tell which is right.
A scenario records what differs from the plan, so when the plan moves underneath it — a new actual, a hire that started — the scenario moves with it. A copied file does not.
Nothing changes and nobody sees it. Your co-founder is not watching you model redundancies in real time.
Months you have closed use what really happened. A scenario changes the future, not your bank statement.
Committed money is signed. Expected money is likely. Speculative money is hoped for. Toggle them independently — and if your runway triples when speculative comes on, that is not a longer runway. It is a dependency with a size.
Floor, expected, ceiling
The gap between the first two is the number to manage.
A fractional CFO or board member builds a scenario inside your model and offers it. You see exactly what it changes, and you accept or decline. The recommendation arrives as a thing that computes rather than a paragraph in an email.