If you turn wet wood to final form, it will warp and oak warps more than most. If you want to kiln dry wood, it needs to be done before the wood is turned to final size. If you put a finished bowl in a kiln it will warp a bit more ... even if it was already at EMC because EMC in the kiln isn't the same as room ambient EMC. Once wood has been thoroughly dried, especially if kiln dried, it isn't going to respond much to seasonal humidity changes.
Moisture meters aren't the best way to tell if a bowl has dried to EMC. Odie's method of weighing is the best way to tell if the wood is dry. A scale that reads grams is essential. You don't really need to know the moisture percentage... all that you really need to know is that the wood has reached equilibrium with its environment (EMC) which be when it is no longer losing weight. If you rough turn a bowl and either bag it or Anchorseal it, it should be adequately dry to finish in about three or four months.
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