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How to Build a Production Critical Path (Time and Action Calendar)

Every order has a date it has to be in stock. Between placing the order and that date sit a dozen or so steps, each owned by someone different, each able to push everything after it back. A critical path is simply those steps written down with a date against each one. It is the most useful planning document an importer can keep, and most small businesses do not have one.

What a critical path is

A critical path, also called a time and action calendar or T&A, lists every milestone an order has to pass, who owns it, the date it is due and the date it actually happened. In large retailers it lives in dedicated software. For a small importer a clear list per order does the same job.

The value is not the list itself. It is that every date depends on the one before it, so when one slips you can see straight away what it does to the in-store date, rather than finding out when the goods fail to arrive.

Start from the end and work backwards

The most common mistake is planning forwards from today. Start with the date you need stock available to sell, and work backwards through each step. That tells you the latest each milestone can happen, which is the date that matters.

In-store or available-to-sell date.
Warehouse receipt, minus a few days for putaway and checking.
Customs clearance and delivery from the port, commonly several days to a week.
Arrival at destination port (ETA).
Ocean transit, which depends on the lane.
Vessel departure (ETD), with cargo cut-off several days before.
Ex-factory date.
Final inspection, a few days before ex-factory.
Bulk production window, the factory's quoted production time.
PP sample approval, which usually starts the production clock.
Bulk fabric and trims in-house, and before that the ex-mill date.
Purchase order placed and deposit paid.

Once every step has a latest date, compare the first one to today. If the order should have been placed three weeks ago, you know now, and you can decide whether to change the freight mode, reduce the order or move the in-store date.

A worked example

Say you need stock in store on 1 March, shipping by sea from Asia with around 20 days transit. Working back roughly: warehouse receipt 24 February, port arrival 17 February, departure 28 January, ex-factory 21 January. With 45 days production counted from PP approval, the PP sample has to be approved by 7 December, and bulk fabric needs to be in the factory around then too.

That example lands the production window across Christmas and the ex-factory date close to Chinese New Year, when factories shut for weeks. Seen on a critical path, that is obvious in October. Seen on a single ex-factory date, it is a surprise in January.

Build buffers into the plan rather than hoping for them. A week of slack before ex-factory and a few days before in-store absorbs the ordinary slips that happen on almost every order.

Which milestones to track

You do not need thirty lines. For most orders these cover it:

PO placed and deposit paid.
Lab dips or colour approved.
Fit and size set approved.
Fabric ex-mill date and fabric in-house.
Trims and packaging in-house.
PP sample approved.
Bulk production start.
Inline inspection, if you use one.
Final inspection passed.
Ex-factory.
ETD and ETA.
Customs cleared and delivered.

Give each one an owner. Many of the slowest steps are on the buyer's side: approvals waiting on your desk, a comment that took a week to send, a decision waiting for someone else. A critical path makes those visible too.

Keeping it live

A critical path written once and filed is a plan. One updated weekly is a tracker. The habit that matters is recording the actual date next to the planned one as each step happens, and when a step is late, moving every later date immediately so you see the new in-store date that week.

Ask suppliers for dates, not percentages. Eighty percent sewn cannot be compared to a plan. Sewing finishes on the 14th can.

The red flags

The PP sample is not approved and the days left before ex-factory are fewer than the factory's production time. The order is already late.
The ex-mill date has moved and nobody has changed the ex-factory date.
A step has no date, only a status.
The same supplier slips at the same step on every order, which means their real lead time is longer than their quoted one.

When a critical path shows an order running late, air freight is often the fix. Run air and sea through the free landed cost calculator to see the real per-unit difference. Open the free calculator

The bottom line

A critical path turns one date you hope for into a chain of dates you can check. Build it backwards from the day you need stock, give every step an owner, record what actually happens, and move everything the moment a step slips. Most late orders are visible weeks ahead on a critical path. Without one, they only show up at the port.

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