yup, it didn't disappear for you because the game technically gave you two blueprints. it doesn't help also that it auto completes the task when you board the tempest. so to really avoid it, for anyone else that is starting a new game: get the bp from Voeld before reaching level 11 (do it at level 9 to be safe, in case you accidentally trigger an exp increase), then craft it right away. but if you accidentally reach level 11 but managed to get the bp beforehand, while in Voeld, just avoid getting back in the tempest, and craft it on the forward station at the outpost. the latter is what happened to me and I was able to complete the task and also avoided the duplicate bp.
