Not all price book products showing in sales order pick list

Not all price book products showing in sales order pick list

Hi - I have a problem in that I have imported 48 products into a new price book divided into 3 sections of four products spread over three years (2015/2016/2017/2018)  48 individual products in total. 
When I then go to create a sales order and I get to the section where it says to "Choose products" for some reason only 24 products show in the pick list and they are randomly listed (not in numerical order) with 2017 coming first before the products in 2015 etc some are even jumbled up in years (not very helpful) How do I:
A - Have all 48 products showing in the pick list?
B - Have them all showing in numerical (date) order?
If it helps we are running professional edition. 
Thanks in advance.