Did your dependents get H4 also renewed at the time of your H1B transfer approval? if yes, then, they would have also got the new i94 and new i797.
But, if you do not go back to old work location (as per approved H1B transfer application) or file a new application immediately, you all have to leave US within 10 days.
No my dependents do not have H4 renewed during my H1 transfer.
So i guess if i dont go back to my old location or my company doesnt file new ammendment my dependents have to leave immediately since their I94 also expired.
Remember, without valid i94, they are accruing ‘Unlawful presence’ in US from the date of denial.
‘Unlawful presence’ has bad consequences for future visa applications.
So, it is better that you talk to your employer and their attorney to quickly plan something concrete.