Submission of additional evidence (i.e.case law) before CIT(appeal) -

You can submit in advance by way of a letter mentioning your intended action in support of appeal for which the notice of hearing is not yet received from your Office.

If notice is received for hearing then also during proceedings you can submit.

-- Vivek
This is your repeat query raised under changed heading. Once it's already replied on 11-11-2019.

Reference to a case law does not constitute additional evidence since it is not an evidence in the first place. Hence, there is absolutely no bar in filing as many case laws as you want before the CIT(Appeals).

thank you very much ..