Hey MyWay… My hubby is on the job too… midnights… for the last 20 years. My take on this is that YOU have to be satisfied with your job(s). If you love what you are presently doing (which is what it sounds like to me), then taking a "promotion" that throws a monkey-wrench into your present situation may be a mistake.
Others may say "take the promotion" and "keep your priorities straight" (define "priorities"… not always MONEY), but if it makes you miserable (NOTHING worse than a miserable cop… this is the voice of experience), and the job can do that to you anyway, then let the new guy get a leg-up… and keep your good deal going (as long as you are OK with your finances and not hurting the family by it).
It sounds like this is only a promotion of title… not necessarily a decent pay raise (not unusual).
As far as "not working 7 days"… you also don’t work 5 days on and 2 days off like everyone else (most cops don’t), so working around the day-shift with the dog cart will be more difficult… if not darn near impossible.
In my husband’s case, he’s turned down the "promotion" to days a few times, because it would cost him seniority and first dibs on vacation time… which is of more value to him.
Maybe think of this…. Once you are eligible for your pension, would you stay on the job or would you keep doing the dogs?? If the PD is just your source of medical coverage and retirement investments etc… and NOT your "passion"… then do what you have to, put your time in where you are serving the community effectively, and keep your dog cart which you "can’t imagine giving up"
If I were in your shoes, and I could stay on top of my financial commitments (and maybe then some), I would take the life where I have a sense of contentment and satisfaction. There are people in this world who never have the opportunity to achieve that… and there really isn’t a dollar amount that compares to it.
Just my humble opinion… best of luck to you in this decision.