SallyL,
It was July in the year that I switched over from DL to CO when I moved to Houston. CO gave me Elete match through January but not for the next year. However, I did not know that at the time. I knew that I would not make it by the end of the year so I called CO's cust. svc. line and explained that I did not know the limitations back in July or I would have waited. I explained that I had only two more trips booked. They asked what they were and calculated the miles. They then put a note in my file stating that if I completed the two trips as stated then I would be given my status for the next year. They did send me confirmation of this via mail and I did get my status 2,000+ miles short of the required level.
Bottom line, call and ask early and get it in writing. They will work with you if at all possible.