H1B - Wages applicable date when amendment is filed with USCIS


New Member
Employee has H1B with valid dates on petition.

Amendment due to location change:
Employee is deployed (Date0) to new project (new customer) at different state within USA.
Continued to work from home from the current location.
Beneficiary wage is increased(Date1), LCA is approved(Date2) and filed with USCIS (Date3).

Employee has moved to new location(as filed in amendment) after 4 months (Date4).
Employee salary is not triggered until physically moved to new location.
Employee is paid from Date4.

What is the date of new wages for employee as per H1B policy compliance for employer?
Is employee required to be paid back-dated to Date1 or Date0 ?