Feather,
Sorry to hear you didn't get your class 1 but keep trying!
I am a pharmacist and my advice to you would be, get plenty of aerobic exercise in the weeks and months running up to your test. I see time until your test is limited so you will have to push yourself hard in order to gain a significant improvement in lung function.
Regular aerobic exercise improves your ability to force air in and out of the lungs by strengthening the muscles involved in breathing. This should see an improvement in your FEV1 and FVC readings.
Aerobic exercise includes running/swimming/cyling for long distances at a moderate pace. I would agree with Shunter and recommend swimming as it uses more muscles and therefore has a greater demand for oxygen.
Use your inhaler in the weeks before and on the morning of your test (check with CAA this is allowed as i'm not sure). Symbicort contains a bronchodilator as well as a steroid. This will open up your airways and should help with spirometry readings. Check out this link for other tips:
http://www.healthatoz.com/healthatoz...spirometry.jsp
I hope this helps and good luck!
Could you please let me know how you booked your class 1 as I wish to get mine in the near future. Cheers