If you open any cutting file, you'll see examples of how to use goto and tag. If you look at the C5 command, it has an example of a pause. I've used the method you describe for cutting numerous parts before and it can get a bit exciting if you run into a second or two delay mounting the new piece. Just be sure you give yourself adequate time for the worst case scenario on changing out the stock. The machine doesn't respond to screams to wait.
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2013 PRS 96x60x12 (Centroid upgrade)
4hp Spindle
12" indexer
Aspire
Rhino
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Ferrari 360
Prusa MK3S+
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