How long dependents can stay in UK after a Skilled Worker's visa ends

[hurawan]

I am working for an employer here in the UK on a Skilled Worker Visa with visa validity till Dec 24 (as per BRP), my company is transferring me to the US on the L visa category, my question is that
a) I need to move to US to join the new project immediately, but can my dependents stay back in UK for a few months to wind up things here before moving to US? if yes then for how long they can stay?
b) If they overstayed in UK so while exiting from UK will they be able to travel on their L2 (dependent visa) to US or they would be sent back to India (our base country)?
c) Will I be able to re-enter UK before Dec 24 on the same BRP? or I would need to apply for a visitor visa? thanks in advance for providing some insight on this.

[Frontier Mole]

The law states they are your dependents and here under your Visa conditions. If you no longer are employed under the skilled worker visa and you have left the U.K. their right to remain is under you, then technically they are without leave to remain. HOWEVER - it will take months for the visa cancellations for you and your dependents to progress through the system. Decide how you want to use that information….
Based on the above your second point is really not an issue BUT for whatever reason after you depart for the USA your dependents were to be encountered or found to be in the U.K. they could be removed to India. This is highly unlikely to happen unless there is a need for hospital treatment or there is an issue involving the police or the Home Office. It is risk. If it were to happen I have no idea how that would impact the USA immigration status.
You would not be able to enter using the BRP card as it would show as invalid after a period of time once your U.K. employer informed UKVI you are no longer sponsored. That process is tied to the digital collection of airline information about passengers and it would show you left the U.K. and would be deemed as automatic visa cancellation without the need to formally cancel your visa. That in itself potentially causes issues for point two above. It might bring attention to your dependents. As I said it is not risk free.

The risk free option involves you and your dependents leaving the U.K. together.

[hurawan]

Thanks Frontier Mole that helps a lot, much appreciate it!