There isn't a pre-written list of what constitutes a substantial change in circumstances, though there are many, many cases exploring whether a particular issue represents a substantial change. Usually the lawyers will provide the judges with the relevant cases to support or rebut whether the facts constitute a substantial change in circumstances. Examples of possible substantial changes in circumstances would be a parent losing a job or getting a new job, coming down with a serious illness affecting their ability to parent, or anything that materially affects or justifies a change to the parenting plan. You should consult with an attorney and explain to him/her your particular circumstances for advice about whether it meets the criteria.
This is not to be considered legal advice nor does an attorney-client relationship exist.
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