hello
our company use Lot size to combine different period of demand together.
in material master data / Lot size data / lot size, you can chose weekly, monthly or even longer.
strandard setting don't have yearly. you can customize "yearly" by yourself.
then sap can gather the "yearly" demand together when run mrp and run out one big PLANNED ORDER or PR. (MRP parameter can decide whether run out PR or plnd Ord)
i recommend you to use planned order, in stead of releasing PR directly.
you only need select a specific date to get the MRP result and release & issue the PR.
Best regards.
Leslie zhao.