I doubt we move JD in the off-season. Management likes to sell tickets, so if we keep him and bring in some fresh blood, management can keep convincing people we're trying to win and sell more tickets. If it doesn't work out, then you start the sale at the deadline. And you can probably keep the money if you move JD and then call up little Vlad to get people to come out to the park. Would be a great way to start the rebuild by getting some solid deadline assets for JD and then having the new #1 prospect come up and rock it.
Tulo only has a few years left on his deal, so once he's done that should line up well with passing it on to Urena or Bichette.
Ideally we should realize though that we're not really going to win it next year, so we really should listen to offers for JD. Just kind of a shame that there's a lot of good 3B out there so most teams challenging don't really need one.