Others have mentioned there being two tickets.
A bit of background: „schema changes“ (i.e. the underlying database changes in an incompatible way) only happen twice per year, so the developers try to cram as much as possible into them (this time, the version of the database software was changed as well). This makes these both a rare, and more harrowing experience.
Other changes happen much more frequently, are more incremental, and usually much less stressful. Many features do not require a schema change and can be implemented right away. Those features, like alternative tracklists, that do, are often split into two parts: the database (schema) change, and the web server (frontend) change. If this were not done, the schema change upgrades would be an even bigger chunk of work.