Warm-ups are not considered part of the email send count, as the warm-up process builds a positive sender reputation and improve deliverability.
Warm-ups start at the midnight after the mailboxes are added and are a precursor to actual email sends, rather than being included in the send count.
In Salesforge, we have the settings panel for each mailbox that looks like this for warm-ups:
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If we click on ''Settings'' we will be able to make settings for the sending limit (warm-up excluded). Keeping the mouse on the Question Mark next to sending limit will show us more details, just as in this screenshot:
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You can check the warm-up stats by going to Mailboxes and clicking on the desired mailbox, hovering the mouse over one of the colors will display more details:
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In this screen, below the warm-up stats, you will be able to find the warm-up code.