Just my opinion
for me get the pup as soon as it’s weaned.
keep it with you when ever you can
im self employed so as soon as they arrive they are with me.
the best two terriers I’ve owned came at 5 week.
terriers do mature quick and I knew that it was a couple of week early but they did everything I wanted and more.
had a Bullx from 6 week and she was fine
If you’ve Time to invest , work etc permitting
sooner is better for me
ATB Tony