the best thing to do is ask your probation officer since he/she would be the person violating you for failing to complete any of your special conditions.
if you require representation for this purpose, feel free to call me: 888-888-7803
By and large, because ARD is not a conviction it is not generally transferred across state lines. Furthermore, the Alcohol Highway Safety School (AHSS) is a very specific class created and implemented according to PA Dept. of Transportation regulations. I do not believe that a class administered in Florida will count as AHSS up here.
However, as the other attorney noted, he best thing to do is call the probation department and ask if they will allow it. Worst that they will say is no.