We now send everything by two methods – either fax and email, email and post of fax & post. If a deadline is approaching we always call to confirm. You probably need to do the same with your clients. There are also computer based SMS services available which allow you to send a text message to a mobile phone from your computer. Email is always a difficulty – some emails get caught in spam filters. Just because an email has been successfully sent from your outbox does not mean is has been successfully received in the inbox of the receiver. If the email MUST get through by a certain deadline then you MUST follow it up with a telephone call.
Always pass on any communication from Immigration to your client as soon as you receive it.