Peg-Intron Delivery - How often?

Just curious if others on Peg Intron tx (once a week shot) are only alllowed to get more than one month at a time delivered/ordered.  Our mail order place says they are only allowed to send 1 month at a time (per Schering's instructions).  The rebetron we can get 3 months at a time (or possibly 6 if its written out for that amount).  I know demand is high and production is behind by Schering.  I would appreciate others input.  We are concerned about our continuted health coverage and since we have it now and it costs us $0 for both drugs I wouldn't mind getting the order in for the rest of my husbands tx.  Thanks for your help.