The necessary aging time depends on the kit, and this is true of all vendors.
My first was a pre-Tavola Barbera (no skins, carboy aged, 1 oz Hungarian medium toast cubes) that was drinkable in 8 months, and has improved. It's coming up on 2 years old (August) and is holding well.
November 2021 I started a Chardonnay, which was drinkable after 6 months is is holding well at 15 months.
Same month I started Forte Super Tuscan and Forte Syrah / Petite Sirah / Merlot, which were barrel aged. They are coming up on 15 months old, and are drinkable, but need more time. This is a combination of the skins & seeds in the Forte kits, and barrel time.
Last spring I started Tavola Pinot Noir and Sauvignon Blanc, both carboy aged (PN no skins, 1 oz Hungarian cubes) and bottled at the 6 month mark. The PN was very drinkable a month after bottling, lighter in body and fruity. The SB was also immediately drinkable.
Early last summer I started Frutta Blackberry and Strawberry, which were bottled at the 4 month mark. Both were drinkable quickly. I have no idea what to expect for shelf life, so they are in the usage rotation.
September 2020 I started WE Australian Chardonnay and Australian Cabernet Sauvignon for my son's wedding reception in Oct 2021. Both were very good at that time, although I was highly disappointed that the Chardonnay we in decline before 2 years of age. The CS is holding well, although I have only 1 bottle left.
Drinkability and longevity are no different for kits than they are any other wine. Heavier wines, e.g., reds or fruits with skin contact, oak, etc., will take longer to age before becoming "good", and generally have a longer lifespan. Lighter reds, whites, and lighter fruits have less chemical changes to experience so they are drinkable sooner, and generally age out faster.
I was honestly surprised that the Tavola reds were drinkable as quickly as they were. IMO this is good, as I can produce a drinkable red in ~6 months, in sharp contrast to my heavier reds that typically need 15+ months.
In the past I had more lifespan from whites, so the WE Chardonnay surprised me, although my son commented that served its purpose and the last couple of bottles declining was not a big deal (which I agree). Based upon that, I'm watching the lifespan of the FWK White and Tavola (no skins) kits. I also note that no two wines are alike, so the lifespan of one kit may be different from the lifespan of an identical kit.