When will the new IMAC be released?
Some this month, some next month.
When Apple announces the release. You are asking other users who do not know more about it than you do, unfortunately.
On the on-line "Store" pages, 21.5" available in November and 27" available in December. However, neither one has a "Select" button link to allow you to order on-line. Your guess is as good as anyone else's.
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