A few Srivaishnava-s wear red Srichuranam and a few others wear yellow Srichuranam; which is the preferred one and what is the rationale behind this?

Please refer to Sudarshanam Plava year Adi month issue 007JUL21001 for answers.
Yellow Srichuranam is natural while red is acquired by mixing. Those who are Vaidik or Vedic wear yellow Srichuranam while some also wear red Srichuranam.