Azadi, I am facing the same as your husband...I will die from boredom, anxiety and the people and relative question, why, when , how..

)
My opinion is as well not to write them an email, just wait week or 2. That what I will tell my husband.
Well I am not expecting to have the visa before the end of July, but just need to be sure that they don't need anything else, all is good, and they are in the decision making level...because in July we will start our 15 month since we sent the application..

So patient will be my best friend (along with the internet) till I get my visa if God wish
I really appriciate your advice, thank you