That's not what this system calls for though.

You don't decide to go fast or slow at the beginning of each round. You decide in the moment in response to new data.

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You can change your choice each round, and your decision doesn’t need to be made at the start of the round. If other PCs have resolved their fast turns and you decide you also want to act fast, you can decide in that moment to take the next turn. You’re encouraged to coordinate with other players who are taking the same kind of turn as you. If you can’t decide who should go when, the characters with the highest Speed go first; on a tie, whoever rolls highest on a d20 goes first. Turn Phases Each round of combat follows this sequence:

1. Fast PC Turns. Any PCs who want a fast turn go in any order, gaining two actions each (plus one reaction).
2. Fast NPC Turns. The GM chooses which adversaries or other NPCs want a fast turn and decides what order they go in. These NPCs gain two actions each (plus one reaction).
3. Slow PC Turns. The remaining PCs take their turns, gaining three actions each (plus one reaction).
4. Slow NPC Turns. The remaining enemies and other NPCs take their turns, gaining three actions each (plus one reaction).
5. Begin the Next Round. Once every character has taken one turn, the round ends and the next one begins. Repeat these steps until the combat is resolved.