"preMainCode" is an internal system message from Aliexpress Standard Shipping, not a physical event. It is not a facility code or a place name. It is a processing step recorded while your parcel moves through the courier's network, usually between sorting and handling scans. Nothing has gone wrong because this line appeared.
No, this message by itself is normal. It almost always appears between routine "Operate success" scans, and in about nine out of ten cases the next update is another "Operate success". It is not an exception or a problem status. A delay is only likely if the tracking stops updating for longer than the previous steps took.
Most often the parcel gets another routine handling scan and continues along its route. Less often, the next updates show export customs clearance, departure from the origin country or region, or the start of import clearance. In rare cases customs asks for tax payment, or the address is flagged as incorrect or incomplete.
Previous status updates:
Next status updates:
With the use of our tracking form you can easily check the status of your package. Also if you want to tracking Aliexpress Standard Shipping and get your package location updates to your e-mail, you can Register on our website.
Aliexpress Standard Shipping — is not the only postal service that you can track at PackageRadar. See full list of postal services available.