Compare two schedule versions and read the redline

Two questions eat a planner's week: "what actually moved since last update?" and "Option A or Option B — which one finishes sooner?" Both are the same job — put two versions side by side and read the difference. Here's how Sketchedule turns that into a change register and a paired-bar redline you can read in seconds and drop straight onto a slide.

Nobody wants the two-hundred-row activity dump. When the sponsor asks what changed this month, they want a sentence and a picture: six dates moved, two activities were added, one dropped, and here's the phase that slipped. When they're choosing between a two-crane sequence and a three-crane sequence, they want to see which finishes earlier and by how much — not to reverse-engineer it from a network in a licensed desktop tool.

The answer to both is a comparison: load version A, compare it against version B, and let the tool do the diff. What comes out is two things — a change register (the list of what moved) and a paired-bar redline (the picture of it). Let's look at the picture first, because it's the thing you actually put in front of people.

Two needs, one mechanic

The monthly update and the options decision feel like different jobs, but the tool does the same thing for both — it aligns two versions on activity ID, works out what changed, and draws it. Only the framing differs:

• "What moved since last month?" — version A is last period's issued programme, version B is this period's update. The redline is your progress-and-slippage story: which phases drifted right, which held, and what got added or dropped since you last reported.
• "Option A vs Option B." — version A and version B are two scenarios you're weighing: a resequenced construction plan, an accelerated bid, a mitigation. The redline shows which one finishes sooner and where the two plans genuinely diverge — the decision, on one page.

Same comparison engine, same change register, same paired-bar picture. Learn it once and you've covered both of the questions people keep asking you.

The comparison, step by step

Take the monthly case: last month's issued programme against this month's update, both exported from your scheduling tool. Here's the run.

1. Open version A. Import last month's programme — MSP XML, P6 XER/XML, or an Excel/CSV extract. It parses in your browser; nothing is uploaded, the file never leaves your machine.
2. Compare with version B. Point Compare at this month's update. Sketchedule aligns the two on activity ID and computes the diff — every date change, every new activity, every one that's gone.
3. Read the change register. You get a sortable list: activity, previous dates, current dates, slip in days, and a status of moved / added / removed (Fig 3). Sort by slip to put the worst movers on top — that's your commentary written for you.
4. Export the redline slide, or share a link. Drop the paired-bar redline into a landscape PDF or PowerPoint slide — print matches screen, your branding on it — or send a read-only link that rebuilds the whole comparison in the recipient's browser, no install, nothing for them to open.

Why a redline beats the tabular claim-digger

Desktop schedulers can compare too — and their comparison is a dense, exhaustive table: every field on every activity, previous against current, thousands of rows deep. It's superb if you're a forensic analyst building a delay claim and you need every atom of the difference. It is useless in a boardroom, and it's slow even for the planner who just wants to know what moved.

A visual redline flips that. The eye reads an offset bar instantly — "that phase slid right, this one held, that's new, that's gone" — with no scrolling and no column-hunting. Where the two part company:

• Instant, not exhaustive. The paired bars carry the signal — direction and size of every move — at a glance. The full detail is still there in the change register when you need it; you just don't have to swim through it to get the headline.
• Board-ready by default. Branded landscape page, RAG-coloured slips, milestones, a title. That's a slide, not a data export you'd then rebuild by hand.
• Anyone can open it. The sponsor choosing between two options, or the partner reviewing the monthly, usually can't open a licensed scheduling layout at all. A read-only link rebuilds the redline for someone with nothing installed.
• Additions and removals are called out, not buried. New scope and dropped scope get their own colour and their own rows — the changes people most often miss in a table are the loudest thing on the picture.

The honest one-liner: a desktop comparison is a claim-digger; a redline is a decision aid. One is built to exhaust the difference, the other to communicate it.

Primavera and P6 are trademarks of Oracle Corporation; Microsoft Project is a trademark of Microsoft Corporation. Sketchedule is an independent product and is not affiliated with, endorsed by or sponsored by Oracle or Microsoft. Figures are illustrative, drawn in Sketchedule.