I would suggest a target which can only be observed before dawn with a large telescope: a faint comet just west of the Sun.
Two candidates listed on The Sky Live are:
They are moving targets, currently about 2 arcseconds per minute of time.
To predict its coordinates for your observation slot, you'll need to get an ephemeris.
Then if your images are successful, you can measure its actual position with astrometry software.
Good data could be useful in refining its orbit.
If you're lucky, a stack of short exposures aligned on the comet nucleus might also make a pretty picture.
Alternatively you could try to get a light curve of an asteroid in the morning sky to estimate its rotation rate. Northolt Branch Observatories in the UK frequently post such results on social media.