Hi,

We had a known issue, described here: https://success.salesforce.com/issues_view?id=a1p3A000001RXBZQA4 related to the performance in API versions 44 and 45.

Now, the issue status says "FIXED - SUMMER '19". Does it mean that we have to switch our classes from 44 and 45 to API 46 (Summer'19)?
I assume that "FIXED" means that old versions should work correctly and there is no need for any actions from our site. Unfortunately, in case of performance issue, it is not easy to verify it on our own.
Could anyone explain how exactly Salesforce deals with these  changes?

Many thanks,
Jakub