The caret (^), followed by the name of the sublist allows one to add a task to the sublist. Unfortunately, this does not seem to work as intended.

@Monish - We have revised our Guide page accordingly. Thank you again for letting us know!
Peggy, Mar 10, 2021
Hi @Monish - Thanks for letting us know. After our last major update for Sublist and Board, we have removed this function for now (adding a task to a Sublist inline). We will add this function back later. Sorry for the inconvenience.
However, you can still assign the task to a Sublist while inspecting the task and using ^. (like below)

Kindly let me know if there are anything else I can help you with. Thanks!
Peggy, Mar 9, 2021
Thanks for letting us know! Could you please reflect the same in your documentation as well?
Monish, Mar 9, 2021
My pleasure 😃
Monish, Mar 10, 2021