in smsdrafts.js, I'm setting isQuestionable/isLookupable to false when recalling drafts; the invalid recipient was already found invalid so we don't need to revalidate it.

The issue happens when adding several recipients in the same time, because validateContact uses `var index = this.recipients.length - 1;` to choose which recipient it needs to update. Which fails when several recipients are added in a short amount of time.