The second LEDC battery life test concluded with an error (reset) after 81 hours.
The LEDC actually continued to operate and keep time, but the processor reset when the hourly chime occurred, the chime can draw up to 90mA and the processor browned-out.
With the chime disabled the clock continued to operate, but I concluded the test. LED brightness became a problem because the batttery voltage was approaching the LED forward voltage.
The final test is sleep 10 minutes, and chime on the hour. This is likely to take a long time so I’ll start another project in-between.