Recently i noticed that at LCSC the status for CH554T is NRD or discontinued. I have some fear that all off these controllers CH551, CH552 and CH554 might be dispear soon. 

Are there any plans to stop these controllers? 

There are no plan to stop those chips.  I suggest you can directly contact with our sales staff follow the email sales@wch.cn, or call 86-25-52638377/88/99/89.