The ruling on one who completes Maghrib with a resident and then shortens 'Isha'

If I am a traveler and I pray Maghrib with a resident imam, and after praying Maghrib I stand for 'Isha' and shorten it, is this permissible? I ask for clarification.
There is nothing wrong with it. If a traveler prays Maghrib with the residents, and then prays 'Isha' afterward in shortened form, there is nothing wrong with it. Likewise, if he prays Dhuhr with them in full, and then prays 'Asr in shortened form and travels, there is nothing wrong with this, praise be to Allah. This is because when a traveler prays with the residents, he completes the prayer, and then he prays the second prayer in shortened form with his fellow travelers.