I've searched for information on this topic, but have been unable to find anything that helps (although, I'm sure the information is out there).
In my spread betting account I am long S&P 500 futures. These futures are labelled US500 SEP-21, so I'm assuming these will expire this Friday 17/09/21, as per 'regular' S&P 500 futures contracts (SP, ES, MES, etc).
What happens if I continue to hold my spread betting long positions through expiration? Will the positions be automatically closed? Or will they be automatically rolled over to the December futures contract?