Massallah pertaining to Isha Salaah

We are a good community of pakstani origin living in Belgium, . Our question is regarding Isha Salat time according to Fiqh Hanafi. We use to pray Isha salat late in the night during summer time for years. All of a sudden the local ulma changed the timetable and pretty much fixed it around 90 minutes from magrib. When we did some inquiries from the local ulama/mufti sahaib, they didnt have any valid explanation and they didn’t object to new timing. When we called back home we found out that our timings were suppose to be calculated around 18 degrees. The new timings are not even close, they are not done with 15 degrees in mind. Nobody knows what it is. Please advise us what to do in this circumstances. We are still reading salat according to old timings and everyone else have problem with us.
In this country Marrakish Muslim Prays Magrib And Isha together.because of short timing of night.
Please reply us as early as possible.and reply us in urdu language if it possible.