So not sure how it's done at Brown but purple allows their pilots to "deviate" or buy a ticket within 3 days of any event. Doesn't even need to be a dh. The money to buy this ticket comes from a deviation bank. You accrue bank money from scheduled DHs that you deviate on. For example, all roads lead to and from Memphis (or wherever you are based), so any schedule DH comes from or to Memphis. Whatever that tickets costs goes into a bank. If you live someplace else you just buy a ticket from home to wherever your pairing starts. If you live in base you can take a company jump to shortcut the trip and/or increase your bank.
There's some nuiances but the best case is holding DHs to your home town. You get paid to be home for 12-30 hours and bank the ticket money for later shenanigans.
All of these tickets are positive space tickets like anyone would buy. Purple gets a discount but you still get all the miles.
Since the rules allow you to buy any ticket within 3 days of an event you could buy a ticket to Cabo San Lucas using your bank money or wherever the best Sbarro's is.
Over 5 block or 11? duty is in business/first.
I'm middle seniority in my seat and I hold DHs to my home town fairly often and accrue about 150k-200k miles a year.