The specific time when the person with an overdue credit card of 20,000 yuan was sued cannot give an exact answer because it involves multiple factors. The following points will be explained in detail below:

1. Bank policies: Different banks have different policies and procedures, and have different ways of handling overdue accounts. Some banks may take legal action quickly, while others may negotiate and repay arrangements with customers over a longer period of time.

2. Contact situation: If the customer maintains communication with the bank and can reach a repayment agreement and repay the debt on time during the repayment plan, the bank may not sue immediately. However, if the customer fails to communicate with the bank or refuses to repay, the bank may take legal action within a short period of time after the overdue payment.

3. Amount of arrears: 20,000 yuan overdue is a large amount of arrears, which may attract the attention of the bank. Generally speaking, banks will be more willing to take legal action to recover larger overdue debts in order to protect their own rights and interests.

To sum up, it is impossible to accurately say the specific time when overdue 20,000 yuan will be prosecuted. Different banks' policies, contact information and the amount owed will all have an impact on the time it takes to file a lawsuit. If you are overdue by 20,000 yuan, it is recommended to contact the bank as soon as possible and seek a solution to avoid possible legal disputes.

Extended information:

Whether it is a credit card or other forms of borrowing, late repayments will have a negative impact on personal credit records. Late payments can result in a lower credit score, increased interest and penalties, and can even have a significant impact on an individual's financial situation and ability to borrow. Therefore, it is important to deal with overdue accounts promptly and properly.

In addition, according to relevant regulations of the China Banking Regulatory Commission, banks can recover overdue debts through prosecution, arbitration, enforcement and other means. Specific procedures and timing will vary based on individual cases and bank policies. To avoid such problems, it is recommended to plan properly when using credit cards and make sure to repay them on time.

Please note that the above content is for reference only. For specific situations, you need to consult relevant professional organizations or lawyers for advice.