If you work overtime in the job you’re being sponsored for, you do not need to update your visa.
There’s no limit to how many hours of overtime you can do.
You can also work up to 20 hours a week in another job or for your own business, as long as you’re still doing the job you’re being sponsored for.
Your work must be in an eligible occupation code.
You can also do unpaid voluntary work.
If you’ll be doing more than 20 hours a week in another job
You’ll need to apply to update your visa so that you’re being sponsored to do both jobs.
You’ll need to:
get a new certificate of sponsorship from your second employer
include a letter with your application explaining that you want to change your current permission to stay