We have his Bird rights, but they're largely irrelevant. The most we can offer him in year 1 of a new deal is the 4th year option we declined, which is $2,803,507**. This is true whether we use Bird rights to go over the cap to sign him, use a mid-level exception, or just use cap space. Also, his cap hold is also $2.803 million, so going over the cap to sign him means that we've probably also kept Amir, Jonas, and Zeller around.
This is also true for any team we might trade him to in the next week, and is why he has no value in trades aside from the small amount of salary filler he can be. If he plays well enough for his new team, he might get an offer larger than they are allowed to make. Even the bi-annual exception is more than his 4th-year option allows. In other words, 29 other teams will be able to make a larger offer if they want to take a look at him.
** - It's possible this number is off by 15%. All players currently under a rookie scale contract will get their salaries increased by 15% next year. This increase won't count against the cap/tax, and the NBA will reimburse teams for the increase. They're just catching up the current rookie scale players to the new CBA increases. Since Young's salary offer is limited by the old rookie scale, it's possible that either he could be offered up to this increased amount of salary ($3.22 million), or that the NBA would treat his $2.8 million salary the same way and pay him 15% extra. I think it is unlikely they addressed this situation, but I'm looking into it.