Company randomly changing components on paystubs

Is it a red flag if a company is frequently making changes to the paystub components? The CTC remains the same but they keep moving around things on the paystub. Like decrease certain component and increase other. I've noticed this occur closer to the tax season. Also, they keep updating the employment portal and later have all employees accept their offer letters again (because they have slyly added some text regarding this shuffling and juggling of components). Is this even legal in India?