Using the CASE Clause with a date range for just Month and DAy

I have the below sample of a code. I am needing to pull data based on a client effective date.. but I cannot include the year. I am getting a syntax error and not sure how to rectify it. Please sample below.

SELECT DISTINCT cli_lev1, cli_lev2, cli_lev3, cli
CASE when FORMAT(cli_eff, 'MMdd') = '1201'
CASE clip_plan then

                    WHEN '1234' THEN '7890'  
                    WHEN '5678' THEN '7910'  
                    WHEN '6438' THEN '8970'  

ELSE clip_plan + '-ERR19'
END
END val_HD04,
cli_lev2 val_REF02
FROM csdatabase.dbo.tbl_cli
INNER JOIN csdatabase.dbo.tbl_clip
ON clip_id1 = cli_id1
ORDER BY cli_lev1, cli_lev2, cli_lev3, clip_net,

I do have other mapping on there that works fine.. i just cannot get it to take a date of month and day only.

SELECT DISTINCT cli_lev1, cli_lev2, cli_lev3, cli
CASE when FORMAT(cli_eff, 'MMdd') = '1201'
THEN CASE clip_plan

                    WHEN '1234' THEN '7890'  
                    WHEN '5678' THEN '7910'  
                    WHEN '6438' THEN '8970'  

ELSE clip_plan + '-ERR19'
END
END val_HD04,