Excel Date & Text Reformat

An Excel file with several thousand rows needs a quick but thorough format overhaul. The only issue I’m facing is inconsistent data presentation—no duplicate removal or missing-value work is required.

Here’s what I need:
• Dates and times must all follow a single, clean standard (e.g., YYYY-MM-DD). Some cells currently mix slashes, dashes, and regional order, so the job involves detecting every variation and converting it accurately without altering the underlying values.
• Text columns require tidy, uniform formatting—trimming stray spaces, fixing broken line breaks, and ensuring consistent case where appropriate—so that filtering, lookups, and pivot tables work flawlessly afterward.

You may use native Excel functions, Power Query, or VBA; whichever route you choose, the final workbook must be 100 % formula-safe (no hidden links or macros unless documented). Please return:
1. The cleaned Excel file.
2. A short changelog or notes sheet outlining the steps you took so future updates stay consistent.

That’s all—straightforward and focused purely on formatting corrections.