Do not mix same-color panels from different shipments of batch production in warehouse. Each coating batch is unique; mixing panels from different batches on single building surface would likely to create color reflection difference to the feeling of naked eyes.
Stockiest distributors should offer small projects of same-color panels from same batch they have in stock. Or at least each surface of a small building must use same-color panels from same batch.
For larger projects, clients are requested to place all panels required for an identical project within one single order.