In my opinion no. Here's the problem. If your being taken of the US employer's payrolls covered by the LCA, i.e. being posted overseas even though its only for 30 days, then you yourself are essentially being benched and working for a company not provided for on your own LCA and you, your self are no longer on a valid H-1B and therefore neither is she, thats my opinion and reading of the situation. I could be wrong and perhaps others have a differen view and analysis of your situation and may weigh in on the issue.
H-4 is for accompanying or following to join H-1B spouse. If your husband is not maintaining his H-1B status, you will not meet your burden to show you were maintaining H-4 status.
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