Send scheduled mail based on different condition

Question

I have 5 types of mail.Within that 2 types are scheduled immediately and rest three types are scheduled after 1 hour.

Now this mails will start triggrering once user set there preferrence from UI.

Example-

 

User 1- select preferrence at 10:00 AM so for user 1 mail triggering will start from 10:00 AM.

i.e. for 2 types got mail immediately and other three types like 10:00 AM,11:00AM,12:00 PM .... 

 

 User 2 - select preferrence at 11:30 AM so for user 1 mail triggering will start from 11:30 AM.

i.e. for 2 types got mail immediately and other three types like 11:30 AM,12:30PM,01:30 PM ....

 

One more thing is there like for same type of mail there can be multiple languege for multiple user.

 

 

So. what process I should follow to acieve all this scenarios together.