Else do nothing SQL query

I have a field, froiexported, in DB table claim3 that is either set to one or zero. I want to run an update where if the criteria in the case statement is met the value in froiexported is set to 1 else do nothing. Below will make my results incorrect every day.

update claim3
set froiexpoted = 
CASE
     WHEN froimaintdate >= dateadd(day,datediff(day,1,GETDATE()),0)
     AND froimaintdate < dateadd(day,datediff(day,0,GETDATE()),0)
     and c1.jurst in ('AK', 'AL', 'CA', 'CO', 'FL', 'GA', 'IA', 'IN', 'KS',        'KY', 'LA', 'MA', 'ME', 'MN', 'MO', 'MS', 'NC', 'NE', 'NJ', 'PA', 'RI', 'SC', 'TN', 'TX', 'UT', 'VA', 'VT', 'WV') THEN '1'
    ELSE '0'
 END