Change invoice recipient email

[gliumio]

Hello,

 

I am looking for a way to send invoice to different email address when some special condition occur.

 

This special condition is some value in custom field, and i know how to check it.

 

I have no idea how to change recipient of the email when that condition is met.

 

I was thinking about using using "EmailPreSend" hook, and then somehow to overwrite the recipient email address. One way maybe to change $client_email merge field? But i have no way to test it at the moment. Anyone know better/for sure? Or have some other ideas?

 

Thanks in advance