Unless you feel
really uncomfortable driving a manual, I'd recommend getting your full licence.
With an automatic, you can only drive automatics; with a full licence, you can drive automatic OR manual.
If you decided now to only get your automatic licence and down the road, realised you needed a full licence, you'd have to take the practical test over again (I'm not sure about the theory test, I would guess not, but it says it's only good for two years, soooo....
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)
For the technicalities:
- You can drive in the UK on your US licence for the first year after you move here
- Leaving the UK on a holiday does
not reset that one year
- You
don't need your provisional to drive here in that first year
- You
do need the provisional to take the UK driving tests, even if it's still within your first year here
- YMMV for whether your instructor wants you to have your UK provisional or if they think your US licence (within 1 year of moving here) is ok for lessons
- The prices for automatic or full licence are the same, so you won't be saving any money by taking automatic; in fact, you'd be spending more if you ever had to re-take the test to get a full licence