Combine notes on customer defaults for tag handling v2

Author: shirgoldbird

docs/xml-and-html-handling/tag-handling-v2.mdx

@@ -15,8 +15,7 @@ Before switching to `v2`, thoroughly test your system and verify any differences
 Additionally, v2 enforces strict parsing of XML. If invalid XML is submitted, the API will return an error.
 
 <Info>
-  Please note that after 1 December 2025, new customers will default to v2 and no longer be able to use v1.
-  Existing customers will continue to default to v1 for the time being, and can opt-in to using v2.
+  Please note that after 1 December 2025, new customers will default to v2. Existing customers will continue to default to v1 for the time being.
 </Info>
 
 <Info>