I found termites 8 months after treatment. Is this normal?

My home was treated around the perimiter by terminix. They drilled holes and filled with chemicals. Just last week, I was moving mulch around a tree about 20 feet away from my house and found about 10-15 of them moving around under the mulch. Is this normal? Is it ok that they are there and not in my house? Will they die when they get close to my house or do I need to retreat?

Thanks...

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