Are you talking about tablets with stabilizer (CYA)? I don't use those, and wouldn't as you suggest, because, along with the chlorine, the tabs are going to be adding a little bit of CYA constantly, raising the total level of it in your pool. Which isn't a bad thing because you'll need more of it when you go SWG. But it means you'll have to keep track of the CYA that's being added, or test for it every few days, or maybe once a week, and adjust the FC level up as the CYA level rises. Which is doable, but kind of a pain. Have you read yet about the FC/CYA relationship? You have to maintain that constantly and correctly, or you risk an algae outbreak. And you don't want that with new plaster. It's certainly fine to do it the way your suggesting, but I would find it much easier to just run the pool as a non-SWG pool, and use liquid chlorine/bleach until just before I'm ready to fire up the SWG, and add the CYA and salt in one go at that point. That way I could simplify my maintenance between now and SWG time. It's exactly how I did mine after my new plaster, and I only added salt and extra CYA a few weeks ago, when I was ready to start my SWG.
Kim will weigh in with her take on it. I'm only sharing how I did it.
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I was assuming "chlorinator" meant SWG.