Matt Barrows of the Sacramento Bee reports that Armstead won't be permitted to join the 49ers until after June 12. The team's last formal practices before training camp take place June 9-11.
Armstead has missed all of the 49ers' OTAs and will miss minicamp because he's still in school.
It was initially believed he'd be able to make it by the June 9 minicamp, but Armstead said Wednesday he's not permitted to join the 49ers until June 12.
Already viewed as a raw project, this will certainly not help his learning process and could dramatically impact his ability to contribute early to the defense.
Armstead was drafted by the 49ers with the 17th overall selection in the 2015 NFL Draft.
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