This looks like a statement that's being written literally, for a one-off execution.
One way to make this simpler: Generate the rows programmatically, instead of writing them literally. For example, in Python:
assessment_ids = ['14010', '14009', '13648', '14026']
sql_statement = """\
INSERT INTO date_pub1 (tranche, assessmentid, date_published, datepub)
VALUES
""" + ",\n ".join(
"('Tranche 26', '{}', '2019-03-08 00:00:00.000', '08 March 2019')".format(assessment_id)
for assessment_id in assessment_ids
) + ";"
print(sql_statement)
produces:
INSERT INTO date_pub1 (tranche, assessmentid, date_published, datepub)
VALUES
('Tranche 26', '14010', '2019-03-08 00:00:00.000', '08 March 2019'),
('Tranche 26', '14009', '2019-03-08 00:00:00.000', '08 March 2019'),
('Tranche 26', '13648', '2019-03-08 00:00:00.000', '08 March 2019'),
('Tranche 26', '14026', '2019-03-08 00:00:00.000', '08 March 2019');