I helped my dad get a match from NW to UA 2P earlier this month, and the confirmation email he received from UA on July 13 (five business days after faxing his NW statement) reads:

Dear Mr dillard8's dad,

Congratulations! You have been awarded
Premier status in the Mileage Plus Program!

This status recognizes your importance to United,
and will make your travel with us easier and more
rewarding than ever.

You will receive your 2005 Premier card in 4-6 weeks. Until then,
simply present your Mileage Plus account number to enjoy all the
benefits of being a Premier member.
And for details about the Premier program, visit www.united.com .

This promotional status will be effective until
February 28, 2006 . To maintain the status, you have
to fly 25,000 paid flight miles or 30 paid flight
segments on United, United Express, United Shuttle
or our Star Alliance partners within a calendar year.

We hope you will travel with us often, and
experience the exceptional service and style
reserved for our Premier members around the world.

Thank you for choosing United Airlines. Enjoy your
Premier membership!

However, when he actually received his membership kit, it is clearly valid through 2/07, not 2/06.