If a person claiming classification of a vessel as a documented vessel eligible for assessment under Section 227 fails to file the affidavit required by Section 254 by 5 p.m. on February 15 of the calendar year in which the fiscal year begins, but files that affidavit on or before the following August 1, the assessment shall be reduced in a sum equal to 80 percent of the reduction that would have been allowed had the affidavit been timely filed.