Were the blood cell numbers on a trend into high or has it always been like this for a while?
Your RBC numbers are on borderline high-normal in my opinion. You can go to a lab in another region in the states and you may fall in into or very close to their "normal range". Reference ranges are statistical ranges that are developed from a group of people who appear "healthy". 95% of "healthy" individuals will fall into this range, and the other 5% who are also healthy(disease free) will fall into the higher or lower sides of the range (i.e. outside the range). In other words, RBC ranges as well as other tests are not constant and changes somewhat between populations. For example, some labs go to the 6.1 range (close to your 6.3), while in our laboratory the high normal is 5.85.
In fact, our Hemoglobin range is (11.8-17.5 g/dl), meaning that you (16.6) fall in the normal range based on our population.
That being said, low MCV can be an indicator of iron deficiency or other types anemia, did they note anything on RBC morphology on your labwork? I think it will be a good idea to get your Iron levels checked, namely (Ferritin, serum iron, TIBC).
How are your other laboratory values that show related to RBCs such as Hematocrit, MCH, MCHC. What are the numbers for your other blood cells (WBCs)?
Assuming the above markers mentioned above are ok, keep in mind that a chronic low oxygen environment may induce the increase of RBCs, such as high altitudes or mild SLEEP APNEA as in your case (http://www.mayoclinic.org/symptoms/high-red-blood-cell-count/basics/causes/sym-20050858). This compounded with your recent surgery I think would have an effect on your RBC numbers.
Overall I wouldn't be too worried about this unless something else comes up on your blood work.