Instead of concentrating on studying for a very important test, one where you should have done everything the first time to avoid failing, the OP is worried about information that no one on SDN is likely to have, and certainly wouldn't give out. It also has no bearing on his clinical training, something they clearly need to be spending a little more time on.
They should take the test at the earliest date possible, as long as they feel confident they have studied enough to pass, so as not to unnecessarily delay their 3rd year clerkships. The USMLE does not, nor will they give absolute time frames on score reporting. This is made clear on the USMLE web site.
Since the OP didn't take the time to read through this information, I assumed that they hadn't had the forethought to examine future subspecialty choices, or that they were so fixated on future subspecialty choice that they forgot to study for step 1.