7) Time is subjective. However, at any point in metatime, only some amount of time has actually been evaluated. Since unevaluated time hasn't happened yet, it contains nothing. Critically, it does not contain any time travelers: unevaluated time can never initiate interaction with evaluated time.
8) If an event would cause a paradox, *and* iterations of that paradox themselves cause further forked timelines containing the same event, that event defines a shatterpoint. More specifically, the shatterpoint is fulfilled if that event does not happen, and violated if it does. Frequently, shatterpoints are localized to specific events which are the only plausible way to prevent the runaway paradox.
9) Transmissions into the future force unevaluated time to become evaluated. Receiving a response may induce a shatterpoint. Use with caution!