Confusion over COA and Visas??

My partner currently has his own business and has a visa which says this. We have recently applied for a Certificate of Approval (we haven't herd any news yet) but i'm just wondering what will happen when we and if we get the COA agreed?
His current visa is for another 2 years, then i think (but i may be wrong), he can apply for indefinate leave to remain. Is this right? he has had is current visa for 1 year already and he also had his first visa for another year before that. If we get agreed for a COA would he be able to work elsewhere or does he need a change of visa? if so, what visa will he need to apply for, to be able to work anywhere? And will this affect his time for getting ILR if he applies for a different visa?

Thank You so much for any help. it will be most appreciated

A COA gives only permission for marriage in the UK. It has no bearing on working nor immigration status.

Thank you very much for your reply. Do you know what type of visa he can apply for to be able to work anywhere and if he does change his visa is the counter reset, so to speak, for the amount of time he has left to get ILR? or does his previous 2 and a half years here already count?

If you are British or have ROA or are settled, then after marriage, he may switch to FLR(M) (285) and subsequently apply for SET(M) (288).

Thank You so so much, that really helps. I think after having a brief read through, he'll probably keep his Business Visa or whatever they call it now. Thank You again.