While Congee being a watery rice porridge or soup, most closely associated with breakfast - either plain or cooked in with pork, chicken or seafood - Congee bowls are large globular bowls particularly recogniced by two pairs of holes drilled into the walls for bronze loop handles. This particlar shape was common in the Kangxi period, but occurs from the last ruler of Ming (Chongchen period, 1628-1644), into the Yongzheng period (1723-1735).
By the early 18th century the same type of bowls but with lion head handles appears as the Camcheng in South East Asia.
If watery rice porridge was given up during the Qianlong peroid I actually don't know, but some time during this period the drilling of holes in the walls of the bowls was - however - given up in favor of lion handles c. 100 years later.
It could be that the round tureens with flat half circular side handles that first made their appearance during late Kangxi/Yongzheng period temporarily doubled as Congee bowls on the local market.