457. If more than one effect applies in the same layer but no dependency is established, then Timestamp order is applied to the effects within that layer and sublayer

457.1. When an effect begins applying, it establishes a time for which it is compared against other Game Effects for purposes of resolving Layered effects as its Timestamp.

457.1.a. Timestamps are not rote values.
457.1.b. Timestamps are relative comparisons between effects and when they began applying to the game.
457.1.c. Timestamps are not referenced by Game Effects in any way. They are only used to finalize layered effects.

457.2. When Rules Text becomes Inactive for any reason, it loses its Timestamp. When it ceases to be Inactive, a new Timestamp is established.

457.3. Effects are applied such that the earliest Timestamp within each Layer and Sublayer applies first, followed by other Effects in that Layer and Sublayer in chronological order.