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/
Kevin Smith Agile Coach, Wikimedia Foundation