The test is only good for 2 years anyway. So unless you are planning a job at a regional or a major soon you don't have to worry about upgrading to the left seat. Which in this current market it will be a while before you could get hired let alone upgrading. So take the 135 test because it's easier. You also have some time before you can even take your ATP ride. Take the test and build your time and then take your checkride at your current employer. Try to take your ride as soon as you are able. That would probably help when the hiring starts up again. GOOD LUCK!!!!!!!