That's a point.
I am probably taking way too many assumptions here, but I think they plan to operate over the cap next season too anyways, which will still disappoint the fanbase, but I am kind of already getting ready for.
They must know or have an inkling based on conversations about what both LMA and Danny want to do (and they know for sure Tony wants another contract). If there are actual LMA trades worked out in the future, they may project to no have the opt outs that the twitterverse seems to think they will have. Danny is probably opting out for an increase. Why wouldn't he? 2nd team all defense and still underpaid relative to Mills and Pau now? no. If he opts out it is for more, not for less. LMA? Who knows. The mystery man both in terms of his intentions and whether he will be traded or not. But I just get the sense capspace in 2018 is an illusion and the only way to get better now is either young player development or trades. And the two big man style they featured all season both in starting lineup and bench last season marginalized the young players that they have.