Are you still requesting a negative brucellosis test for bitches when you do shipped semen? When you do a side by side?
How far in advance of the breeding are you comfortable with the result?

No, yes, and no more than 1 month

Side by side, YES, and a month sounds good.

I test my boys every six months. They have never bred a bitch naturally and will never do so. It is imperative you know what the facts are and test frequently.