about shutdown fixed asset

hi,my client requested stop depreciation for some of fixed asset for maybe 3 months,it means no depreciation posted to those fixed asset during the period of shutdown.

then i tryed to shutdown those asset in asset master,then i check depreciation,i found those already posted depreciation will be reversed after shutdown.

but i just want to stop depreciation ,i dont want to reverse those already posted depreciation,can somebody tell me how to do that?