Is it superior to pray Isha at its time or praying close to Fajr time with Tahajjud?

What would be more rewarded? praying isha at it's time before the halfway point, or let's say by accident, I go to sleep and happen to get up 30 min before fajr, so I pray isha , and some tahajjud. Which would be the more rewarded scenario?

Assalamu alaykum

In the name of Allah, the Inspirer of truth.

It is superior for men to perform 'Isha salat with congregation whenever that takes place at the local masjid. Thereafter, get up for tahajjud and perform the witr salat with it the latter part of the night. For women though it would be superior to perform the 'Isha as late as possible before sleeping, as long as it is before half the night has passed, then wake up for tahajjud. If this is not possible then it would be superior to perform the 'Isha salat early then awaken before dawn for tahajjud.

It is disliked to delay the Isha prayer beyond half the night. However, witr can be delayed and performed after tahajjud. This holds the most reward.

Wassalam

Abdurrahman ibn Yusuf