I've heard that digging a plant up twice in one season will result in the plant not blooming the following year. So you should be lining out for next year's sales, not this fall's. Plants go thru a rapid growth period about two weeks after they stop blooming so that's when I line out. Timing will vary from plant to plant and is an ongoing process here in zone 7. I've already lined out the early bloomers into single fans that quickly increase into doubles and by the time they are shipped in the spring, they may be triples or more. Lining out makes selling so much easier because you aren't lifting a big ole clump to mail plants to multiple customers and having to ship them all at the same time (or replant for later shipment which is hard on the plants). You are never sure how the clump will come apart or if there might be injury to the crowns in the division process. So lining out well in advance gives the plants plenty of time to recover and increase from dividing before selling them to your customers. And your customer will get a "whole" plant free from crown injuries with a full root system. I cringe when I hear about people just sticking a shovel into a clump to get a division...which always results in injury to the plant being sold.
