Cover letter ideas in a company where you applied some years ago

Hi everyone, Hope level IIIers are having good time, same as (even better than) those who passed level I & II. As we are in the middle of the transfer season I’d like to apply in a company were I have been rejected from years ago. With more maturity and experience (not especially in the field they are looking at but my soft skills might be valuable for them) I have a chance to go through the screening but I’ll have to develop a new cover letter not just from scratch but explaining why I evolved and why they should consider my application again. What are your advices? As someone already succeeded doing that? Thanks for the support, hope I’ll land the job afterwards. Paul