What is the ruling on delaying the Maghrib prayer by half an hour after the Adhan, and the Imam prolonging the recitation so that the prayer finishes half an hour before the Adhan of Isha?

Performing Salah at the beginning of its prescribed time is among the best acts of devotion and a hastening to good deeds. The Prophet, peace and blessings be upon him, was asked: "Which deeds are most beloved to Allah?" He replied: "Prayer at its appointed time." Hastening to perform Salah at the beginning of its time is better than delaying it, because it is the most beloved of deeds when performed at its recommended time. Similarly, an Imam delaying the Maghrib prayer for half an hour after the Adhan and prolonging the recitation is contrary to what is preferred, especially if it causes hardship to the congregants. It is known that the time for Maghrib extends until the disappearance of the red twilight.