Due to a large Call of Duty update, ProtonVPN servers in the US are under high load, which is expected. However, performance is unaffected as we have safeguards in place to prevent performance degradation despite the high load. More information can be found here: https://www.reddit.com/r/ProtonVPN/comments/i4aj77/did_call_of_duty_release_another_update_every/
Paying ProtonVPN users will get the Call of Duty updates much much faster than free ProtonVPN users. It is possible to upgrade by logging in at account.protonvpn.com.