Gradual Send Vs. Fixed Send Time
First, I have read using segments and recipients time zone, and the pros and cons of using a fixed send time - thank you for these insights,
Part 1 - Basic question - short version:
If I choose gradual send, there is no checkbox for “determine recipients at send time”, so my guess is that Klaviyo does not re-evaluate who qualifies for the segment/list at send time, if I pre-schedule the send – is this correct?
I swear there used to be a check box for the gradual send option, but I can’t prove it. Also, I found 2 help articles that *seem* to contradict each other, so I’m not sure which is correct. Below are links to the articles, with relevant screenshots.
Understanding campaign schedule and send options:

How to change when a campaigns recipients are determined:

Part 2 - Longer version
When my company migrated to Klaviyo 2+ years ago, I was encouraged by the onboarding specialist to use gradual sends so that inbox providers wouldn’t get as many requests all at once, leading to less results of spam-like sending. For reference, we have almost 58,000 active profiles – I honestly don’t know if that is a lot or not, and how that number would affect inbox providers if all the emails were sent at once – but I am concerned about our emails getting blocked if I choose fixed send time.
However, I would really like our campaigns to be determined at send time, especially with BCFM coming up. Most of our subscribers are in the US/Eastern time zone, so I have been using that zone for the gradual sends. In addition, we have a custom integration and I’m not confident that the time zones for all our subscribers are correct, so selecting recipient’s time zone is also kind of scary.
Does anyone have any experience with gradual and fixed sends they can share? Or any insights as to whether I still need to use the gradual send to avoid being seen as spam?
