Wireless to wireless number portability
According to the FCC:
"The Porting Period
Your new telephone company can usually give you a good idea about how long the process will take. To keep the process as short as possible, the FCC recently clarified that companies may not obstruct or delay number porting by requiring you to provide excessive personal information before porting your existing telephone number. In addition, the FCC clarified that validation for a simple number port should require no more than the following information: (1) 10-digit telephone number; (2) customer account number; (3) 5-digit zip code; and (4) pass code, if it applies.
The FCC is also considering imposing additional requirements to make LNP more efficient, including shortening porting periods for simple ports.
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For a wireless-to-wireless transfer, your phone number should work within a few hours of your request to change wireless providers.
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A wireline-to-wireless transfer may take several business days to complete. Ask your new wireless company whether you will be able to continue using your current wireline number during the transfer process. There may be a period of mixed service, when you essentially have two telephones with the same number during the adjustment period.
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If you port from a wireline phone to a wireless phone, your wireline long distance company will not move with you. Your long distance service will generally be provided by your new wireless company, but you should verify this with the new wireless company before changing service providers."
http://www.fcc.gov/cib/consumerfacts/numbport.html
24-48 hours can be considered a "normal" number portability window when something like the iPhone comes out and large numbers of telephone numbers are ported. However, seeing that you stated that everyone but T-mo can call you indicates that the global routing tables have been updated but Tmo hasn't released your number. If they haven't released it by Monday afternoon you should call them up and inquire about the holdup. They may be short staffed over the weekend, though the process at this point is extremely automated.
And I also work for a telecommunications company.
