Next offseason
90 percent they wont this season to try to avoid repeat luxury tax
They can use it this year and still avoid the tax, provided they send out sufficient salary in the trade (or in some other trade).
Any deal for a good player is going to cost us SOME player or two. I'm dubious anyone is going to just give us a worthwhile player for nothing.
Right now, we have, I believe, ~15.7M of space under the tax so without anything else moving, we would be limited to a salary of that much that we could use of the TPE.
But as I said, we ill have to send out at least one player .. well, I'm not going to be specific because someone will get mad at me for wanting to trade their favorite player. But let's assume some Player X who has a contract making 3M.
So we send Player X and a draft pick to the other team in exchange for a highly protected 2nd round pick (which will never convey) in one transaction. This creates a small 3M TPE, but more importanly, increases the room we have under the tax up to 18.7M.
So the other team then sends us the player we want, making a salary up 18.7M, which we absorb into the TPE and we stay under the tax.
So basically, the more salary we send out, the bigger contract we can take back in this way, up to the limit of the TPE, without going into the tax.
I think there is a good chance Danny will try to use it prior to the Trade Deadline, because gaining such a player could really boost our chances in this playoff season. But only for a solid player who fits what Danny wants.
On the other hand, if he waits until the off-season, since we will have (in that scenario) avoided the tax this year and will HAVE to pay the tax next year (because Tatum's salary kicks in), Danny will no longer be constrained to have to stay under the tax and will be able to use up the entirety of the TPE without having to shed salaries. So at that time, he could trade for a player making up to the 28M or so of the TPE.
He would not be able to accept a free agent player in a sign & trade, though.