This starts as a normal callback.
If enabled, then the system will call the customer,
Currently on busy tone etc it just stops there doesn't retry - there is an idea open to add this, - so there are some limitations to be aware of. On voicemail and live person detection it can go to an inbound flow (recommended approach). From there you can add logic, like greeting the customer, even for voicemail maybe having a menu incase it was a false detection, or ask the customer they still need to speak to someone etc. Then you can apply logic to increase the priority, like calculating the total wait time to convert to priority, then transfer to ACD with that increased priority so that they are next in queue. At that point they are just like any other inbound interaction in queue.
There are a number of impacts that should be considered however, see my post here: https://community.genesys.com/discussion/customer-first-callback-impacts-on-ewt#bme5a5e3bb-fbb7-4f05-81f4-0192bc3aa703 where I raise a few of those in a couple of posts, haven't really had the right answers to those, but should get you thinking about some of those impacts to consider.
------------------------------
Anton Vroon
------------------------------