For increise SLA  I need to change Azure LoadBalancer SKU,

Azure LB Basic don’t have SLA, different is for Standard SKU. 

Don’t is possibile to change the sku with a upgrade, the only solution is create a new LoadBalancer (Standard)  e  configure it with the configuration of old LoadBalancer (Basic).

Luckily Microsoft have release a procedure for made it. 

https://docs.microsoft.com/en-us/azure/load-balancer/upgrade-basic-standard

We need check if our LoadBalancer is Public or Internal (No Outbound or With Outbound)

For any choose we have a script to use. Very easy. 

What are the steps of the script?

1- Save and change (with new free IPs) the frontend IPs of Basic LoadBalancer (the script support only 5 Frontend IPs, for more IPs you manually pass the IPs)

2- Create a new Standard LoadBalancer with the configuration of basic loadbalancer  (Frontend IP, Probe ecc..)

3- Migrate the backend pool 

In my upgrade we have been  a ten minutes of downtime.