Wingflex,
The only way to bypass someone who is senior to you on the list, is for the more senior person to not have the upgrade criteria hours. And you are right, some guys are being held back as they don't have the 3000hrs on an EK type, or the 4000hs over 55t when their number comes up.
Do you really think a new joiner should plan on bypassing the 1200+ FOs already on the list?
Upgrade at the moment is averaging 4 to 4.5yrs on the Boeing, 5 to 5.5 yrs on the Bus. A decade ago it was averaging 18mths to 3yrs, this was when we had 250 FOs on the list. The last Boeing presently on order will be delivered by year end 2013. A350 delivers start after this, how long after will depend on if it works out of the box or not I guess.
By all means join, but do so with a realistic idea of progression times.
The Don