I was going to say Alpha-numerical order (which I am sure has been stated before somewhere) ...
but as you point out when AWLS Brumbek mixed textures is listed in Wrye Bash the alphabetically named come after numerically named, and as per the help file...
"sub-packages are installed in the order they appear" - so, 00 would be overwritten by 01, 01 overwritten by 02.
And if numerical first, as in Brumbeks mixed textures ... alphabetical follow further down the sub-package list, the alphabeticals will overwrite the numerically named sub-packages.
I have always made bains with numerically named sub-packages, and using the wizards for AWLS, I did not give them a second look until now.
In your case if you want yours to overwrite all sub-packages before it you would have to name it starting with z - something
(This is why I like my Install Order to read Highest is visually lower, because it ties in with the order of installation of sub-packages ... bottom of the list (Highest) wins).
Edit: Thankfully this doesn't change my Guides, because I dont use mixed alpha-numeric examples