when to switch from 4k veg light to 3k

If you want to have more internodial distance, give more distance to the plants, or dimm your light. those quantumboards are very powerful I start my grows with awide distance, and come closer later...... and yes you can grow them with " smaller lights" too Ive started my plants for along time under 2x26 watt Led, for around 20 days. Girls growing well and looking great