Can anyone let me know, how do we get the Last Updated time of a particular CONS

You can show the now function in a text field in the tempo form itself and display the text field only if the constant is modified.
Assuming that the updated constant is being stored in a rule input, you could use the code below :
if(
rule!APN_isEmpty(ri!updatedValue_text),
{},
a!textField(
label: "Updated time",
labelPosition: "ABOVE",
value: now(),
readonly: true(),
refreshAfter: "UNFOCUS",
validations: {}
)
)
Hope it helps.

You can show the now function in a text field in the tempo form itself and display the text field only if the constant is modified.
Assuming that the updated constant is being stored in a rule input, you could use the code below :
if(
rule!APN_isEmpty(ri!updatedValue_text),
{},
a!textField(
label: "Updated time",
labelPosition: "ABOVE",
value: now(),
readonly: true(),
refreshAfter: "UNFOCUS",
validations: {}
)
)
Hope it helps.