Launching a loyalty programme has one bad moment, and it happens on the first day.
Your best customer, the one who has ordered every month for three years, logs in and sees zero points and the lowest tier. Beside her, someone who bought a mug last Tuesday sees the same thing.
The message that sends is the opposite of the one the programme was built to send.
What the import does
It runs your existing WooCommerce order history through your earning rules and assigns the resulting balances.
Your three-year customer arrives with a balance that reflects three years of orders, and probably at a tier. The mug buyer arrives with a small balance. The programme starts by acknowledging what already happened rather than pretending your shop opened this morning.
Why it changes the launch
Two things follow from it.
Your regulars are immediately in. They log in, see a substantial balance and a tier, and the programme reads as recognition rather than a new scheme asking them to start earning. Some of them will redeem something in the first week, which is a return visit you got from launching.
Tiers are populated from the start. An empty top tier is a target nobody has reached and nobody believes in. A top tier with your actual best customers in it is a real thing that other customers can see is achievable.
Deciding how far back
How much history to include is a judgement call.
All of it is the generous option and can produce large balances that cost you real money to honour, particularly if your redemption rate is set high.
A limited window, say the last year or two, is more common. It rewards current customers without capitalising the whole history of the business into liability. It also better reflects what you are trying to encourage, which is recent and continuing custom rather than someone who shopped with you once in 2019.
Worth doing the arithmetic on total points issued against your redemption rate before committing, since this is the one moment where you create a large obligation in a single action.
Running it
From Perkie’s import screen, and it is intended as a one-off at launch rather than something to repeat. Ongoing orders earn as they complete, through the normal path.
After it runs
Customers see their balance and history on their rewards page as though it had always been there.
It is worth telling them. An email saying "we have launched rewards and you already have 4,200 points" is a considerably better launch announcement than one asking people to start earning, and it is the single best use of the import.