Short answer
Usually yes. The subclass 100 relationship is normally the same partner relationship that led to the subclass 309 visa.
The sponsoring partner for subclass 100 is generally the Australian citizen, Australian permanent resident or eligible New Zealand citizen who was specified in the subclass 309 application.
Home Affairs generally needs to be satisfied that the spouse or de facto relationship is continuing at the subclass 100 decision stage.
There are limited situations where the relationship may have ended but subclass 100 can still be considered, such as where the sponsoring partner has died, family violence has occurred, or certain child custody, access or maintenance issues apply.