Historical Rules · 24 September 2021
Rule 613.7k
Official source text from the 24 September 2021 Rules release
If two or more objects would receive a timestamp simultaneously, such as by entering a zone simultaneously or becoming attached simultaneously, their relative timestamps are determined in APNAP order (see rule 101.4). Objects controlled by the active player (or owned by the active player, if they have no controller) have an earlier relative timestamp in the order of that player’s choice, followed by each other player in turn order.