Right around a week from when I sent my original e-mail. This is the reply they send to your request so you might be able to cut out a step by including the required information with your request:

"Thank you for contacting the MileagePlus Service Center.

We will be happy to consider your request for Premier Silver, Gold,
Platinum or 1K* status through our Premier Status Match Challenge
promotion. We will match your current status in another airline’s
frequent flyer program with an equivalent Premier level in the
MileagePlus program. Some airlines, including Star Alliance member
airlines, are not eligible for this program and the match may not be
processed at the airport.

To get started, please attach** a copy of your most recent statement
showing year-to-date activity and elite status or your membership card
from the other airline (that clearly identifies your current elite
level), along with your MileagePlus account number. If you prefer to
mail your information, be sure to include your e-mail address.

E-Mail: [email protected]

Mail:
MileagePlus Service Center
Attn: Premier Challenge
PO Box 6120
Rapid City, SD 57709-6120

We will respond to your request via e-mail within 10 business days. If
your status match is approved, we will upgrade your account to an
equivalent Premier status for 90 days from the date of approval. Here is
how you can retain that status:

-For Premier Silver, fly 10,000 Premier qualifying miles or 15 Premier
qualifying segments within the 90-day conditional period.

-For Premier Gold, fly 17,500 Premier qualifying miles or 22 Premier
qualifying segments within the 90-day conditional period.

-For Premier Platinum, fly 25,000 Premier qualifying miles or 30 Premier
qualifying segments within the 90-day conditional period.

-For Premier 1K, fly 35,000 Premier qualifying miles or 40 Premier
qualifying segments within the 90-day conditional period.

Qualifying flights must be operated by United or United Express with a
United flight number and credited to your MileagePlus account. Flights
operated by United that have a partner’s codeshare flight number and
United codeshare flights operated by any other airline, regardless of
how the ticket is purchased, do not qualify.

Once you meet the appropriate threshold, you will remain a Premier
Silver, Gold, Platinum or 1K member through January 31, 2013, unless you
qualify for Premier status based on the standard Premier qualification
requirements posted at www.united.com . You may only qualify for the
same Premier status level as your matched status. If you do not meet the
flight requirement within the 90-day period for the status we are
matching, you will return to your previous level of membership and will
not be able to request a Premier Status Match Challenge for another five
years.

For complete details, please click on the following link:
www.united.com/statusmatch

We wish you success in qualifying for a status match.

* We only match Delta Air Lines and American Airlines to 1K status.

**The following file types may be included as attachments in your
e-mail: doc, pdf, rtf, txt, xls, bmp, gif, jpg, jpeg, png, tif and tiff.


We appreciate you taking the time to contact us.

Regards,

XXXXX XXXXXXXX
MileagePlus® Service Center

We appreciate your participation in the MileagePlus program and your
support of United and our partners. We look forward to serving your
travel needs again in the near future. For MileagePlus program
information, please visit www.mileageplus.com."

Last I heard only Marriott & Hyatt give you status while completing the challenges is that still the case?

Yes, you do have to reply and accept their offer. The 4 months challenge period will start once they received your answer and upgraded your account to Gold.

I just got my status match today. Can anyone confirm I'd actually get status until Jan 2015 if I complete the 35k after July 1st?

EXP matches are done seldom and you have to have equivalent..meaning 1K. I have never seen them offer EXP for a lower status..makes no sense to do that

Through my company (that I work for), United offers free status matches up to 1K without any traveling requirements. When is the best time to do that? July 1st or July 15th so I can get the United status till Feb 2015.

After July 1st.

Thank you, SQCXEKflyer! Unfortunately for me, that is the same address I had used before, and the one which got me a reply saying they would forward my inquiry to the right people... still waiting.

Thanks. Did that today, got a reply 15 minutes later, and my status has been upgraded to Gold. Valid until 30/09/2013. On hindsight, I should have waited for that reply just a bit longer (until right before my next Oneworld flight), so the status could have lasted a bit longer than to september, and giving me more chance to retain Gold.

I tried to request a status match on Air India with my current United Premier Platinum status and got the following response:
Dear Mr. Jain,

My company has a corporate status match with AA. They provide a link to a special AA online form. It asks for current status and airline. It does not look like they require documentation so it is very simple.

Has anyone gone this route? If I wait until July 1st will it take me through 2014?

Will any airlines match a SW companion status? That's all I got! :)

Spirit? :D

My company has the same thing for American and also offers a match to United up to 1k without a challenge. As someone without status, can anyone recommend a way to take advantage of this?

This...

;)