The Custom Bitlinks section is where all of your branded and customized Bitlinks will live as an Enterprise customers. To be considered a custom Bitlink, it will need to have both a Branded Short Domain (BD) AND a customized backend.
For example, bit.ly/bitlinks would not be considered a custom Bitlink because it does not have a Branded Short Domain.
"es.pn/2yxklu" would not be considered a custom Bitlink because while it has a Branded Short Domain, it doesn't have a customized back half.
An example of a link that would live in this section is "es.pn/SuperBowl"