Not knowing "exactly" what trans you have I am kind of guessing, BUT I believe this is actually normal. Most electric od transmissions will prevent the OD from coming on until the trans is at a certain operating temp.
As long as it works fine after she is warmed up I wouldn't be worried about it.
At 68,000 I would do a fluid change anyways, don't think it will help, but it surely won't hurt.
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