Transact SQL :: How To Update Table In Many To Many Relationship

I am having challenge to update the redemption table from the multiple card activation table.  I want to update the redemption table with the activation date closest to the redeem date.  

For example:  Redeem date 20071223, I need to update the top row Date, Year, Period fields from the Card activation table.

Redeem date 20071228, I want to refer to the second row in the Card activation table date 20071228.  
Redeem date 20080316 or later, I want to use the last row in the card activation table date 20080316.

How to modify the update query to select the right activation row accordingly?

Below is my partial code I used but it always pick the 20071223 date to update my redemption table.

 CREATE TABLE #Card
 (
       [CardNumber] varchar(20)
 ,[ Date] int
 ,[ Year] int
 ,[ Month] int
 ,[ Period] int
  )  
 
[Code] ....