It was Lucknow - Chhapra Express. AFAIK In the 2014 budget It was announced as a Daily Express train but after the inauguration, it was a tri-weekly service. Later on due to political influence 15072 LJN - Mau was introduced in its slot 20:25 from LJN. Post Covid it shifted to GTNR and CI. CI helps it as at CPR platform remains available and mainly didn't get blocked due to shunting works. As there is a third line between CI and CPR.