Dear Hamed, hhamedk
I apologize for some possible confusion, but there was no development in this regard started or even planned.
Diving a little deeper into your request I have doubts into the problem that you would like to solve:
1) Currently there are no notifications in case the block is by balance and you would like to somehow set up these notifications. How do you see this can work? Let's assume the current balance is 200$ and the block is set to take place when the balance reaches 50$. I do not think notifications by days can happen in this case. Maybe this can be a notification aka 'notify the user when the balance is ... ' What are your thoughts here?
2) In the block by days functionality, by default the notification is sent each day within 5 days prior to the day of the block with the message '5/4/3/2/1 days left...'. If you set the negative value for the block by days, besides the notifications that I just described, you will get messages aka 'your account will be blocked soon'.
Is this functionality not enough? Do you want to get more/fewer notifications? Or customize them somehow?
Wialon Hosting Product manager, Gurtam