If you return to the industry after this time or you find once again you have a need for an MSIC and it is before the date the card would have expired, you will need to sign a statutory declaration stating there has been no change to your criminal record and your card will be re-issued to you with the original expiry date.
Even if there has been no change to your criminal history the issuing body may decide that new background checks will need to be undertaken. If this is the case your new card will expire two to four years from when this new check was conducted.