In PA, my 1st DUI (violation)was in 1996 my second DUI (violation) was in 2008. My 1st (conviction) was Feb of 1999 my second (convition) was Aug of 2009. After 2007 they only go back 10 years when considrring if you fall in the 2nd DUI category or 1st. A 2nd means Interlock... Do they go from... violation to violation... or... conviction to conviction... or... Convition to violation??

But they will also be looking at a third perhaps,

Conviction to date charges brought is common ( date of offense)