I had a job in a district for 10 years. Only 2 of the 10 years were "contract" and credentialed years. In other words, I'm not HIGH on the pay scale because the first job was a "classified" or para educator position. So, when the resume's go out - do I notate this or just lump everything together as in ABC District - 19XX to 20XX ? In other words, would districts prefer hiring someone for less pay? They already have to pay more for the masters.
In all honesty, it may be a disadvantage. It all depends on the district. I would say to really sell the fact that you have more experience over a new teacher which will benefit them in the long run.