Working backwards from the last delivery date of 23 December...
I never like to send a guitar out on 23rd December because it gives you no room for error if there is any problem at all with the delivery. Therefore I would like to be sending everything out by 22nd December (Tuesday).
For your own peace of mind I would suggest that I can only promise a delivery for Xmas if the order is in by Friday 18th December. Saturday and Sunday orders are "possibles" and Monday is a "you'll be lucky!!".
Please note that the main factor is the time it takes to set the guitar up (IE going through the workshop for quality control and setup).
Shop customers benefit from the fact that they can buy a guitar and return the guitar in the new year for the setup if things get too tight pre xmas.
Please note that not all guitars are always in stock when you are ordering online and if you want to guarantee a Happy Christmas PLEASE order your guitar NOW or as early as physically possible. If there is any issue with availability I can let you know and we can possibly work out alternative arrangements.