"@Pratik - I too had trouble with this but through trial and error I figured it out, and its pretty simple. 1: Delete (or move) the .p12 file on computer that was made in the cydia impactor folder. 2: Delete the Yalu app from iOS device. 3: Make sure your device is displayed and Drag the Yalu IPA into impactor just like the first time, give it your apple id login info & click okay to proceed past the revoke preexisting certificate warning and very shortly Yalu app will be on your device again. 4: Just like the first time you need to enable trusting your new certificate in settings > general > profiles.
- Now you've got 7 days and 7 hours that it's good for again, unless you have an account that's an official paid account - then you've got longer =)"