How to sum up 4 weekly buckets demand to one weekly bucket ?

Hello Macro Experts,

We release demand at SKU -Plant to weekly buckets for next 18 months.

For a few codes demand would be very less (X Number). For those codes we want demand to be released to 1st bucket of every month, As I believe its not possible to release such , I'm looking for a Macro which can sum up 4 weekly buckets demand and update in 1st week bucket and delete for 2,3,4 weekly bucket.

TIA