Your application is locked in on the day you submit. Your age and IELTS date can't be affected. Even if the application takes 24 months. (which yours won't btw)It does on the CRS and FSW score though. But yes I understand that it won't bring the score below the cut off, what I am not sure off is how would IRCC want to process it.
It's only in the case of a refusal where you need to get back into the pool that these become a matter of concern. So I'll say you have nothing to worry about.