I'm adding to this. I'm also in Southern California on COX and have had horrid lag for the last week+ and have tried everything to fix it including calling our ISP. Nothing has worked.

Platform? PC
Have you tried using a wired connection? I'm always hard-lined
Internet Service Provider: COX
Region/Location: Southern California
Separate Modem and Router or Hybrid? Separate
Are you using a Firewall/Anti-virus solution? If so, which ones? Windows Defender
Does the issue only happen with specific characters or all characters? I only play on one character.