What would happen if I change the time delay of a live Klaviyo flow?

Hi there,

I have a confusing question in regards to the Klaviyo Flows. We currently have a live flow as below:

Trigger: When someone has the tag XXX → wait 1 day → 1st Email → wait 1 month → 2nd Email

After an internal discussion, we  would like to change my time delay to this:

Trigger: When someone has the tag XXX → wait 15 mins → 1st Email → wait 3 days → 2nd Email

However, there are still 2 customers in the waiting of 2nd Email. Can anyone tell me what would happen if I change the time delay? Would those 2 customers be skipped? Or would they receive the 2nd Email immediately?

Thanks for helping out!