Hi @john john ,
With "Allow 'Fill-in' choices" function enabled you can have users fill in their own choices if their item does not appear in the list. So it is not a issue, "MY NEW CHOICE" will not be saved inside the Choice field options and this behavior is by design. Per my test, like you said we can reuse this new choice field. It seems like this new choice field is added to the New item form instead of the Choice field options(in column settings).
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