Refrigeration of Cream Liquor
Between 6-18 months is the usual number. Refrigeration isn't required, but certainly will help. Bailey's claims to be fine for two years, but no other site backs up their claim.

I can't find anything specific on "Jackson Morgan Cream Liqueur"; they don't seem to have any sort of expiration information on their site. I'd err on the side of caution and try to knock it out inside a year, and refrigerate when possible.

As with many other dairy based products, it's incredibly obvious when it begins to spoil. Taste, color, and texture will all go notably off before it becomes harmful to drink.

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