When using a sensitive word or expression in your new company name, you'll typically need to provide a letter of non-objection from the relevant authority, any additional documentation or justification to  to demonstrate that you have the right to use the word or that it accurately reflects the nature of your business.
When including a sensitive word in the new company name, the process of changing the company name will typically require ordering the name change by post. This entire process usually takes between 5 to 10 working days to complete.