The default (it appears) is SMBv1 + SMBv2.Is SMBv3 the new router default in FW v3006?
Currently in 3006.102.4 the Samba protocol version choices are:
SMBv1
SMBv2
SMBv1 + SMBv2
PS: The GT-AX11000 doesn't support 3006.x firmware. It is on the 388 firmware track (3004.388.9_2). The GT-AX11000 Pro supports stable 3006.102.4 and beta 3006.102.5-beta2.