After the coldboxes feature and the warmboxes feature. /s
Real answer: I generally don't do ETAs, because look how often a random snapshot, website issue or other crisis interrupts my work on the next Wurst update. It happened multiple times just this week.
When I do confirm that a feature is coming in a specific version, that usually means I'm already done implementing it and thus I really can guarantee that it will be in that update.
But early estimates for something that sits deep down on a todo list and hasn't even begun development are just pointless.