If I'm being paid 197 days, and a typical teacher is paid 187 days, those ten days are covered by:
Summer Marching Band
Every Saturday in which there is All Region, Marching Contest and Region meetings.
(By the way, that adds up to a ton more than 10 days)
STOP WORKING FOR FREE!
Stipends pay for extra duties outside the normal school day in a normal school calendar - but if your stipend doesn't include an allotment for drillwriting/arranging, DON'T DO IT
It's NOT part of the job to donate thousands of dollars worth of your skill and expertise to your program every year! Demand compensation for it!
classroom teachers are also only on 187 day contracts so they should be paid for that work during the summer. Same for the band directors in that district if they were not on extended contracts and that time worked was outside of contract time they should have been paid. However, if a high school band director is on extended contract, (more that 193/197) and they are working most of the summer, what better thing to do than write drill and arrangements during the summer on the clock. It is part of the job.