I did the boom with a set of 39 .. First boom !what an experience. I so enjoyed , I will do it again. 4 months turn around is one third of a year, thinking about it everyday for one third of the year. My response to your suggestion of 4 groups of 15 or 2 groups of 30 at one time, maybe you, however I can not imagine having 3 or 4 spreadsheets at one time to work with.. and all the mail to be delivered into my mailbox, mailing out correctly, the postage fees, were about $48.00 and making all those blocks on time and it oh it would drive my postman to change routes. I am in for 15 this time. I am looking forward to it.
Cuppy