How are your emails sent in a specific time slot?
When you add contacts to a sequence, you have to choose the time slot of emails sending. Contacts will be randomly splitted and contacted in this time slot in order to keep a "human look-alike" way of sending emails. Here are two use cases:
If you add 5 contacts at 10.00 am, the first email could be sent at 10.18 am and the four other will follow, all before 11.00 am.
If you add 100 contact at 11.00 am, e-mails will be sent earlier in order to split them equally between 11.00 am and 12.00 pm.
How do emails drip through time ?
When you add contacts to a sequence, several elements are considered to make sure emails are sent on the best timing:
your generic quotas (that you can find here) represent the maximum volume of emails you can send through this email address
your sending quotas that you define when adding contacts to a sequence (1 and 2 on the pic below). Only considering this specific contacts adding to the sequence, you'll never be able to send more emails than as defined on the sending quotas. Your sending quotas can never be higher than your generic quotas.
day and time for sequence launching : no email will be sent before this timing
the number of days between 2 steps of your sequence : if you set that email 2 is scheduled 3 days after mail 1, any mail 2 that will be sent will have waited at least 3 days after its mail 1 was sent
hourly slots chosen for your sequence steps : if you set that email 2 is scheduled on the 4pm - 5pm slot, then no email 2 from your sequence will be sent before this time slot
the schedule chosen for your sequence (more information here)
Following your sequence launching, our algorith compiles all elements in order to make sure that :
you do not go over your generic quotas
you do not go over your sending quotas
your followup emails are sent at least X days after the previous emails, X being set up by yourself in the sequence
your followup emails are never sent earlier than the time slot you defined for them in your sequence
Consequently, your emails can be delayed. For instance
if your set your emails 2 to be sent on 4pm - 5pm
but that you defined sending quotas as 10 emails per hour
if you have 20 emails scheduled, then 10 are sent on the 4pm - 5pm slot, and the next 10 are sent on the 5pm - 6pm slot
Other example :
if you set your emails 2 to be sent on the 4pm - 5pm slot
but that you have several running sequences and your generic quotas are reached for today
then your emails 2 are delayed for tomorrow, starting on the 4pm - 5pm slot