Hello Colohio,
We see that FaceTime calls are still coming through even with Do Not Disturb enabled on your iPhone. We certainly understand your concern, and we'd be happy to look into this with you.
We were able to test this and discovered that audio FaceTime calls do not come through when Do Not Disturb is enabled. However, when trying a video FaceTime call, the call was able to come through. It appears that the audio calls act like the Phone app, which does not allow calls when Do No Disturb is enabled, but when using video the calls still come through.
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