Do you actually have to be employee for business visa? Not all business owners work for company. WP require it for sure, but maybe worth to explore is owning the company just enought for business visa.
It depends on your visa. If you have SAME retirement, marriage, ED, elite visa etc you registered on first place, there is no need to update. How ever, if you enter with NEW visa or exemption, new TM30 is needed.
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