SharePoint Search - Sort by managed property alias not working

Hi All, 

I've mapped "RefinableInt01" to an integer type crawled property in my tenant, called 'ows_ApplicationOrder' and add an alias as 'AppOrder'. 

Let's say my data are 1,3,10,5.

Now in my REST search query if I provide RefinableInt01 as the sort list, it works as expected and returns 1,3,5,10. 

https://<tenant>.sharepoint.com/_api/search/query?querytext='ContentType:+"App+Link"'&sortlist='RefinableInt01:ascending'

But if I provide my alias 'AppOrder' in the search query as follows it doesn't work as expected and returns 1,10,3,5.

https://<tenant>.sharepoint.com/_api/search/query?querytext='ContentType:+"App+Link"'&sortlist='AppOrder:ascending'

Any idea why? Is sortlist doesn't honor the Alias? 

Supun