It would wholly depend on what strikes the US engage in and whether Iran can take further strikes if it retaliated and how it would retaliate. A lot of ifs and maybes at this moment

I am not an expert on Iran's missile capabilities. I know there are fears they may target Qatar's and Saudi's oil infrastructure, but the US has enhanced defences in the Gulf to protect Qatar, especially post-Israel/Iran strikes.

If they use standoff munitions (long range) aircraft then they need to move just within a range for aircraft to take off and be able to launch their missiles from

I am not sure, I am not an expert on naval warfare or manoeuvring, but it did take the US a few weeks to build up forces off the coast of Venezuela.

Maybe. The USS Abraham Lincoln Strike Carrier Group has been mobilised to the region from South China Sea.

The US may have also provided forewarning about potential strikes to lessen retaliation from Iran.

The #Pentagon has apparently ordered a Strike Carrier Group (USS Abraham Lincoln aircraft carrier) to mobilise to the ME (CENTCOM region) amid rising anticipation of imminent #US strikes against #Iran

Anticipation of a potential attack rather than actually knowing.