If I create a new field which will now replace previous fields, is it possible to hide this field so it can't be used going forwards without deleting it and all the data that has already been entered in it?
You could hide the field using a field configuration scheme.
Take a look here for more info :
In the past, Portfolio for Jira required a high degree of detail–foresight that was unrealistic for many businesses to have–in order to produce a reliable long-term roadmap. We're tur...
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