When ordering your handmade wedding invitations, it might be best to decide when you want them to go out to your guests and work backwards.
Things to consider -
2-3 weeks proof and print time.
1-5 business days shipping time.
How many days for your to hand address your invites.
1-5 days for guests to receive them once mailed.
These are all practical things to think about giving yourself at least 4 months prior to your wedding date as a general time frame.