Assalamualaykum sheikh, is it permissible for someone with incontinence to make wudu shortly before fajr and pray Tahajjud and fajr with the same wudu. Or is it better for someone with this condition to do something else during the last third of the night like making dua?

Ustadh AbdulAziz al-Haqqan

You can make wudhu and pray, and when the athan happens he makes wudhu and prays the sunnah and fajir.