As of last night:

#discovery-analysis-backlog is now simply #discovery-analysis[1]

#discovery-analysis-sprint is now a milestone within #discovery-analysis, and will (often) be displayed as "Discovery-Analysis (Current work)" [2]. That means it also appears as a column within #discovery-analysis.

The names could still change slightly, depending on the preferences of the analysis team.

[1] https://phabricator.wikimedia.org/project/view/1850/
[2] https://phabricator.wikimedia.org/project/view/1241/