I'm pretty sure that that is the plan. It is about leaving Eureka/Mars Stadium permanently larger and better equipped to stage larger scale events (sports, concerts, community festivals, pageants and displays). A study commissioned by the Andrews Government in 2018, managed by the Ballarat Council and conducted by Price, Waterhouse and Cooper made a number of recommendations which weren't publicly released but some snippets have leaked out over time. It is believed that the latest upgrades at the stadium (the entrance gates, the concreting of the hill, upgrades to the player change facilities etc.) were immediately prompted by the analysis of that study. The study also identified major long term objectives that included replacing the existing light towers and expansion of the stadium to hold 16,000. The Western Bulldogs were consulted as key stake holders in the study and they recommended that the stadium be expanded to 20,000 but agreed that it should not be a 20,000 capacity all-seater. It's believed that they agreed to a compromise of 15,000 seated and 5000 standing.
This was reinforced earlier this year when the Ballarat Council released their priority project of advocacy to both State and Federal politicians ahead of the elections see pages 6 and 16 of the linked PDF docucument: https://www.ballarat.vic.gov.au/sites/default/files/2022-01/Priority Projects Advocacy Overview.pdf