STK bundles will still be delivered.
Existing customers (pre 5.4) will still have STK based templates and may migrate directly to 5.5

MTE & STK page to become a MTE page that:

• contains a brief paragraph about STK and points people to 5.4 doc for more info
• has a sub page re installing stk (since the bundles will still be delivered). Content about installing stk is currently in the "STK changes in 5.4" page.