Custom wait until a dynamic date minus X days

Hello all,

I kindly need your support on the correct syntax & functions to be used on a Wait node (Custom)

I'm required to wait until X days before a dynamic date

Example:
End Date = 2025-02-10T18:00:00Z
X = 2 days
Calculated datetime from Custom wait = 2025-02-08T18:00:00Z

Could you help me with the correct expression to be used?

Thanks,
Salvatore