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I think that "Started" just means that the time/date when the proposal begins has passed and the end date hasn't yet been reached. In that particular case, today's date is between May 1, 2022 and May 1, 2023.

In order to start receiving SBDs, the proposal would have to receive more votes than the "return proposal", currently listed in the first slot (i.e. more than 47.2 million SP would need to vote for it).

One point that may not be obvious is that the proposal can bounce above/below the "return proposal" any number of times, so it is possible that funding starts, stops, and starts again repeatedly as people adjust their votes.