create table dropme_ldr_test(f1 varchar2(100), f2 date);

LOAD DATA characterset cl8mswin1251
INFILE *
replace
into table dropme_ldr_test
FIELDS terminated by ";"
( F1 POSITION(1)
, F2 "CASE when :F2 not like '%24:00:00' then to_date(:F2,'yyyy-mm-dd hh24:mi:ss')
       else to_date(REPLACE(:F2,'24:00:00','00:00:00'),'yyyy-mm-dd hh24:mi:ss')+1
	  END"
)
BEGINDATA
First Rule;2018-06-19 11:30:00
Second Rule;2018-06-19 24:00:00

Table DROPME_LDR_TEST:
  2 Rows successfully loaded.
  0 Rows not loaded due to data errors.
  0 Rows not loaded because all WHEN clauses were failed.
  0 Rows not loaded because all fields were null.

SQL> select * from dropme_ldr_test;
F1              F2
--------------- --------------------
First Rule      19.06.2018 11:30:00
Second Rule     20.06.2018

SQL> 

LOAD DATA characterset cl8mswin1251
INFILE *
replace
into table dropme_ldr_test
WHEN x <> '24:00:00' -- грузим регулярные записи
FIELDS terminated by ";"
( x1 filler POSITION(1), x filler POSITION(*+11) -- вырезаем подстроку из поля с датой-временем для проверки условия WHEN
, F1 position(1)
, F2 DATE "yyyy-mm-dd hh24:mi:ss"
)
into table dropme_ldr_test
WHEN x = '24:00:00' -- специальные записи требуют вызова sql function
FIELDS terminated by ";"
( x1 filler POSITION(1), x filler POSITION(*+11) 
, F1 position(1) -- возврат к началу логической записи
, F2 terminated by whitespace  "to_date(:F2,'yyyy-mm-dd') + 1"
)
BEGINDATA
First Rule;2018-06-19 11:30:00
Second Rule;2018-06-19 24:00:00