There apparently is a time limit, I'm not sure what it is yet, but mum got her request for passport photos on Tuesday (she's visa exempt), we sent them off on Tuesday night, but the request said it was an urgent request as now that the processing of the application is complete there is a deadline to complete landing by. They didn't say what that is, it will be on the landing documents when we receive them hopefully next week. We're just driving to the border to land though, we only live 5 minutes away from it.