وَإِذَا أَرَدْتُمْ نَقْلَهَا فَاسْتَأْذِنُوا الْمَسْؤُولَ.
When you intend to move them, ask the responsible person for permission.
The clause introduced by “idhā” limits the instruction to the circumstance of intending a transfer. “Fa-staʾdhinū” is a request-form response to the condition, linked by fāʾ.
The directive does not require asking permission at every moment. It requires doing so before the specified action. Omission or careless placement of the condition could expand the scope of the instruction beyond what the speaker intends.