When do you stop calling it a preview and start treating it like the show?

I’m interested in the point where a longer work-in-progress stops getting rebuilt after every outing. Early previews feel like permission to move whole sections around, try an ending that may not survive, cut ten minutes and put five back. But at some point I assume you need a stable version long enough to learn what the actual show does rather than what tonight’s rewrite did. If you’re developing towards a Fringe run, when do you start freezing the running order and making smaller changes instead?

When a bit only works inside the longer show, do you keep it?

I’ve got material that feels weak as a standalone five but makes much more sense once the audience knows the earlier stuff it’s calling back to. I’m torn between treating that as evidence the bit is doing a useful job in the show, or as a warning that it can’t stand on its own. When you’re building longer material, do you still expect every section to survive independently, or are some bits allowed to earn their place mainly through context and callbacks?

When do you stop adding new bits to a longer show?

I’m finding the dangerous thing about building a longer set is that every decent new idea feels like it deserves a place. At some point that has to stop or the show never gets a shape. If you’re developing towards a Fringe-length hour, do you set a point where new material goes into a separate pile and you only work on what’s already in the show? Or do you keep letting stronger bits replace weaker ones right up until the run?