"Network-level backdoors", a.k.a. CALEA have already been allowed for two and a half decades. That wouldn't change, but this would prevent them from forcing Apple to backdoor the encryption on your iPhone, for example.
I would say it's safe to assume that the law would protect data that stays on your phone, but would not protect communication. So you could encrypt the contents of your phone but phone calls, SMS, and IM would still be possible to back door.