There have been a few discussions on this topic in the community but there still doesn't seem to be a clear cut answer to this. Here's what exists today:
Our instance's default timezone is "(GMT-04:00) Eastern Daylight Time (America/New_York) (EDT)". On November 1 - when daylight savings time ends in the US - will all date-related assets (e.g., calendar tokens), report subscriptions, etc.) be adjusted automatically? We're primarily concerned with the existing times defined in calendar tokens for active events throughout our instance. I really hope we don't have to adjust these manually after November 1.
My assumption; yes.
Marketo has a System DateTime Token (System Tokens Glossary - Marketo Docs - Product Docs ) which I assume is automatically updated on DST. It would make sense to have all campaigns / wait steps connected to this system DateTime.
Makes me curious on what will happen if you schedule a campaign to launch in the 1 hour void
That's my assumption as well. I really hope someone from Marketo can respond here with a formal/official answer.
Marketo does automatically adjust for daylight savings time.