When a bullish order block turns into a bearish order block or a bearish order block turns into a bullish we call this a breaker block. You can compare this concept to the support turn into resistance, it only uses a different concept, but the same principle. The SMC Indicator offers a setting where you can plot breaker blocks, so you can identify them more easily. Below this there is an image that shows this feature in live action (blue box).
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How to enable the Breaker Block Feature?

Step 1: head over to the SMC Settings

To enable the feature simply head over to the indicator settings.

Step 2: Enable the Breaker Block Feature

When you are inside the SMC settings - locate the "Order Block (OB)" section and make sure to click on the Order Block Style dropdown and enable the Breaker Blocks. Voila.

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