question about the s/o gig
 

new here, been reading all the posts, intersted in s/o position (since not quite competetive for the f/o position yet...)

s/o is "based in HK and are recruited to the pax fleets"
-does that mean you can be recruited to any pax fleet domicile like LAX or SFO? or just pax fleet outta HK?

previous posts mention s/o upgrade is around 3-4 years as of now
-since you get a "seniority number at the bottom of the common Aircrew Seniority List" does that mean when you actually upgrade that you are ahead of direct f/os hired after you?

I'm also curious as to which are the senior bases as of now? (especially curious about both US pax and frieght base seniority)

any feedback would be greatly appreciated. thanks-