They told me that they did a job at Harrington Park last week that on the first pier hole was 0.9m but ended in a total of 161lm with some major depth before they hit solid ground.
Pics below, might get some of concrete over the weekend. They said the slab would be poured maybe Tuesday arvo but if not would be done on Wednesday.
View from the Garage
View from Alfresco
Concreter ready to measure