Non-Immigrant B eVisa Application Issue

[farandaway]

Looking for advice please:
Yesterday I applied via London Embassy for eVisa 'Non-Immigrant B / Business Visit visa', and I paid the fee.
Today the Thai Company who I will work with for 2 months said that I will need a 'Non-Immigrant B / Employment' visa, so I can submit a WP32.

I am contacting the Thai Embassy in London to see if I can simply change the application, so I don't lose the money, I don't know if this is possible or not. 

Or maybe I can cancel the Business Visit application, and reapply from the beginning, even if that means I will lose the money.

Or maybe I can apply additionally for the Employment visa without cancelling the Business visit visa.  i.e. Maybe it is possible to have 2 visa approvals and then choose which one I use on arrival in Thailand...?

Does anyone have any experience with this kind of a situation??
Thanks in advance.