Update Global Blanket Purchase Agreement expiration date

Hi,

We are trying to update the Global Blanket Purchase Agreement expiration date lines through Buyer work center , but there is more than 4000 lines in this GBPA .
I have updated the lines manually till 1001 but this is not an efficient way.

Is there is a way to update the lines by a script or by and alternative way instated of updating manually?

PS: By update I mean why need to clear the expiration date for all the 4000 lines.

Please support.

BR,