The jig also uses the plug on the end of the neck to mount, which is where the Vintage Neck's truss rod adjustment goes.
The Modern construction necks use a 1/4" fingerboard slab too, which gives more material to work from.
This jig was made in house, many many years ago only for the 25.5 scale" necks. Unless demand warrants moving this rare-order option into CNC, it's doubtful that further developments warrant the many test necks and time away from production to bring this option to market.
When I worked there, I had loads of people from the Sevenstring forum hounding me about 7 string options, and scallops, and emotionally, I'm sure I could support their argument, but you have to look at this from a business perspective.
Economics = supply/demand.
The bulk of the demand for Warmoth products are the bread & butter Fender style bodies & necks with your basic custom options. That's what they are going to supply because that is their primary revenue stream.
Infrequent order options like 7 string and scallops, while some of us (myself included) love these options, the orders for them are so far and few between that further development of them is not cost effective.
During the year that I worked there, I had 1 order for a Seven String body/neck, and maybe 2 or 3 scallop or half scallop orders. That's one year, only one rep. Not likely multiplied by the 5 reps working there at the building housing the world's largest inventory of replacement bodies/necks and pickups.
Ask the Aaron. For every body or neck that goes to market, upwards of 5-10 were test built that can never be sold (opportunity cost) as well as the time they spend on the CNC machine interrupting production of the product that has a quick turnover to produce revenue. Compound that with an already low profit margin industry, and the demand for payroll, compensation insurance and health insurance, and then you might be able to fully appreciate Warmoth's perspective on this as a business, and not just a company satisfying a creative or emotional muse.