Probably so. My volume is around 750k email per day roughly.
Recently they started tinkering with spam filter, which worked fairly well before. Now it doesnt work - good mails go to spam, spam garbage goes inbox. Support tried - I'll give them that - but almost all their advises were either not working or working just partially.
My guess is they integrating "AI" with spam filter, hence the quality decline.
I use just use help-> Open ticket and getting one response per day (this is to address timely responses). Granted I am in UTC+7, but from company as big as FastMail you would expect support around the clock.
