Stuck at the progress at the moment, because waiting for handlebar...

Can this be verified as true info? I can not find proper info about that. Frame is 86,5 mm and I am installing GRX600 2x10 crankset. I got three shims 1/2/3 mm width
Also ordered specific tool for BB T47, 48,5/49 mm width.

in my direct experience with ultegra crankset and without shims it touch and grinds the BB. with 1mm shim is ok. maybe grx crankset is different. just do a try.
i cant post a pic now, but i can do it later, if you wanna see grinded nds crankarm and bb

@c.etzo: are you happy with the saddle, is it comfortable or is the 3D printed layer too thin?

I've done 20 hours in 2 weeks and it's ok ! Comfortable

mine was ok and bearings have a very tight fit.

maybe tantan and sequel uses a different factory or QC? or maybe is just luck

@c.etzo: I am not sure what you are saying.

I took a look at the fristcomponents page.
SRAM specifies T47-85.5 so I have a BB like this: https://www.firstcomponents.com/wp-content/uploads/2018/10/C47-985-85-point-5-assembly-A1.pdf
TanTan specified T47-86.5 so I would go for something like https://www.firstcomponents.com/wp-content/uploads/2018/10/D47-392F-86-point-5-92-FSA-assembly.pdf

There is a 1 mm difference between these BBs. Can I simply use a T47-85.5 in a wider frame shell?

86.5 or 85.5 is the width of the bb frame shell, so if tantan specify that the frame has a 86.5, i'll go for it

look at hambini guide to t47 https://www.hambini.com/engineering-guide-t47-bottom-bracket-standard/

just received same frame, and build is in progress:

Frame/Fork/handlebar/seatpost: Sequel DCFR 26 / size 52 / cockpit 90mm x 38cm frane weight 1060 gr without hardware, fork 385gr  uncut
Bottom Bracket: T47/24 by kactus
groupset: Shimano Ultegra di2 12 full with 52/36 chainrings and 11-30 cassette
pedals: Favero Assioma Powermeter
saddle: Ryet 3d X6-3d  weight 170 gr
wheels: ICAN aero 40
Tires: vittoria N.ext tubeless

they sent me round bolts for FD hanger, making impossible to setup, ordered flat ones to solve.
had to cut a little of seatpost (6cm), full inserted cant reach my saddle height.
have painted frame and fork with a removable vynil paint in chameleon color.

added some weights

i've ordered a size 52 black from sequel store, shipped in august and i'm waiting for delivery (hope soon)
i'll paint it by myself with a vynilic removable paint in chameleon colors

looks like a workswell 256 disc ( i have it)