Almost all validators in the HDX network has more than 64 delegations. This set of delegations is determined by the number of HDX tokens in the delegation, not by the order of delegating. For example, a delegator delegates 65th in the queue, but his delegation has more tokens than the delegator who delegated 64th and receives rewards currently. Then the delegator with more tokens displaces the delegator from the 64th position and enters the set of delegators receiving rewards. And the delegator who previously held the 64th position is dropped from this set and ceases to receive rewards.