Probably be much easier detailing what’s left in the US! Can’t be much.
The bombers…. The last item in the box.
During Midnight Hammer the B-52s flew west towards Guam and DG but were a decoy with the B-2s attacking direct from the USA.
If this intended, as suggested, as more of a sustained campaign I would expect they would deploy to DG and perhaps Fairford, closer to Iran, to allow more sustained operations.
B-52s and B-2s deploying will be a good indicator that operations are near.
Having said that, the B-2s could do a first day wave from CONUS - and the number of tankers in Lajes has gone up to 13…