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For example, if the Specified offset of topic1-1 is set to 10, when  when new partition-1 is discovered with an offset range of [0, 5], all messages in the range of [0, 5] will be consumed. If When new partition-1 already has more than 10 messages written when it is discoveredis discovered with an offset range of [0, 15], then consumption will begin from offset 10. If partition-2 has no specified offset, when new partition-2 is discovered with an offset range of [0, 515], all messages in the range of [0, 515] will be consumed.

Using "Earliest" ensures that the same behavior of consuming offsets for new partitions is maintained.

The timestamp only affects existing partitions and can start from a certain point in middle of offset range . It should not be used for new partitions.

TimestampOffsetsInitializer 

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• For the new partitions before this timestamp, they will be immediately adopted using the latest version offset once discovered, instead of waiting until the timestamp. It also depends on how many messages are written between partition creation and discovery, which is very unpredictable and unreasonable.
• For the new partitions created after this timestamp, it will be equivalent to the earliest.(For continuous streaming jobs, this is more common.）

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The timestamp only affects existing partitions and can start from a certain point in middle of time range. It should not be used for new partitions.

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