I've been told to replace our month-end Excel pack with Power BI, and I'm the one who gets blamed if the numbers change

Month-end minus two days. I spent the morning doing what I always do: refreshing the links between the four workbooks, applying the regional adjustments from the operations email, and checking the summary tab against the ERP export. It balanced first time today, which never happens, so I took the win and screenshotted it.

At the steering meeting, the finance director asked for the third time when the pack will be 'in Power BI like we agreed in January'. I said we are progressing. We are not, really. I have a half-built PBIX from February where the revenue total sits 40,000 off the pack, and I still do not know if that is my model or an adjustment buried in workbook three.

Afternoon was the quiet panic hour. I listed what scares me: the manual adjustments nobody else knows about, the exception rules for two odd customers, the fact that Carol in ops emails me corrections that never touch a system. If the first Power BI month does not match the pack to the pound, the directors will call the project broken, and it will be my name on it.

What I actually need is permission and a plan: an inventory of what the pack really does, an order to migrate it in pieces, a parallel month where both versions run and I can explain every variance, and an honest line about what stays in Excel. Give me that and I would start tomorrow.