Store no more than 2 recent version chains

Using Incremental scheme with Full backup followed by 5 incremental versions. Repeat this process, keeping no more than 2 copies of recent version chains.

Despite setting backup with these paramaters, appear to accumulate more than 2 recent version chains, and I must manually delete chains older than the most recent two.

Is this a bug? Or, is the program not set up correctly?

Screen shot of my Backup Option screen attached.

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Second question.

When I wish to make a reserve copy of the above backup, I want to create a duplicate of at least 2 full backups with their most recent incremental version chains. However, when I select the backup reserve copy, I get a full copy with each run (no incremental copies). Is there a different way to get a duplicate of the 2 full copies plus their incremental version chains on a second drive? Selecting reserve copy does not appear to achieve this. See attachment of setting.