In Subscriptions > Overview > I checked Digest Mode, which is defined as:
"Merges your notifications into a single email, sent at the interval you specify. "
Under Preferences I set the Send Interval to be Daily.
I receive a couple dozen emails each day. They all have a subject of "Subscription Digest for..."
Each email only contains a single item, so it doesn't appear to be a "digest."
It clearly is coming more than once a day, so doesn't appear to be following the set Send Interval.
Is this a bug or am I misunderstanding the settings?