missing timelines after user preferences change

Windows 10 v1709, Resolve Studio 15.1.
When user checks "Load all timelines when opening projects" and restarts Resolve, timelines previously not loaded are missing from the bins and from the "Select Timeline" dropdown list.
Repro:
1. Restore a PostgreSQL 9.2 DB dump (Resolve 12.5) into PostgreSQL 9.5 using Project Server
2. Upgrade restored DB, optimize, connect DB in Resolve's Project Manager
3. Load a project into 15.1, the default state of "Load all timelines when opening projects" is off
4. Load several timelines out of maybe twenty-thirty timelines available in the project
5. Under user preferences enable "Load all timelines when opening projects"
6. Restart Resolve and load the project again
7. All timelines not loaded in step 4. are missing from the bins and the "Select Timeline" dropdown list
I tried the steps two times and got consistent outcome. Note that even with "Load all timelines when opening projects" checked, a very complex project that takes over six minutes to load on V12.5 took just twenty seconds to load in V15.1, likely indicating that all timelines are either not loaded into RAM or that they are truly purged from the DB during an earlier step.
When user checks "Load all timelines when opening projects" and restarts Resolve, timelines previously not loaded are missing from the bins and from the "Select Timeline" dropdown list.
Repro:
1. Restore a PostgreSQL 9.2 DB dump (Resolve 12.5) into PostgreSQL 9.5 using Project Server
2. Upgrade restored DB, optimize, connect DB in Resolve's Project Manager
3. Load a project into 15.1, the default state of "Load all timelines when opening projects" is off
4. Load several timelines out of maybe twenty-thirty timelines available in the project
5. Under user preferences enable "Load all timelines when opening projects"
6. Restart Resolve and load the project again
7. All timelines not loaded in step 4. are missing from the bins and the "Select Timeline" dropdown list
I tried the steps two times and got consistent outcome. Note that even with "Load all timelines when opening projects" checked, a very complex project that takes over six minutes to load on V12.5 took just twenty seconds to load in V15.1, likely indicating that all timelines are either not loaded into RAM or that they are truly purged from the DB during an earlier step.