At the deadline, there are usually about 41 days left out of a 186 day season.  That means that at the deadline, a player's cap hit will only count 41/186 of their annual cap hit on the new team.  Therefore, a team's projected cap space for the year can fit 186/41 (4.53) Annual Cap Hit at the deadline. For example, if a team has $1M projected cap space for the year and that accrues, at the deadline they can add $1M * (186/41) = $4.54M in Annual Cap Hit.