If you're fairly sure that you'll need your tax credits back after a month then it's just increasing the margin for error to transfer credits back and forth.
Also, you have used more than half of your credits for the year so the Revenue will likely only transfer them on a "week one basis" which means he will not get the cumulative benefit of them.
If you are fairly certain to return to work in September you will get the benefit of August's tax credits then.
If you are unlikely to return to work in September then you could then transfer the credits to your husband on a week one basis and he will get the benefit of your credits for the rest of the year and then get a review after year end to make sure you haven't lost out.
Sybil