First, congratulations on your success in the deferred prosecution program!
In answering your questions, the DOL requires the ignition interlock device for 5 years if this was your second offense (1 year for a first offense) but the Judge has the discretion to add extra time. If you drove with the IIL for a certain amount of time before the interlock requirement began, you receive credit for that time. That being said, if you have only had the device for a total of 3 years and 3 months, including the time with the IID, then the math does not add up. Make sure that you do not remove the device until you have confirmed with the DOL that they have removed the IID requirement from your license.
You are required to have SR22 insurance for 3 years following the end of your license suspension. The DOL should be able to confirm the end of the SR22 insurance requirement as well so I recommend confirming the date with them because cancelling SR22 insurance early would result in an immediate license suspension.
Best of luck with everything.
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