Neoblackdragon

Umm in each season finale, the new rangers tend to lose their powers and also dont make their identities known.

mmpr rangers lost their powers
Zeo- Rangers changed powers
Turbo- old team left and new team lost powers
In space- Team currently has powers
Lost galaxy, team currently has powers but in another galaxy
Lightspeed, Team currently has powers
Timeforce Team currently has powers but most are in the year 3000
Wildforce team has lost powers
Ninjastorm team has lost powers
Dinothunder team has lost powers
Spd- team has powers but live in the future
mystic force- unknown but assumed
Overdrive current team


But anyway

<b>In the Episode Forever Red from Wild Force it has about 10 red rangers. All except wes and eric from Time Force, who come from the very distant future, the rest were from the same era...</b>

Forever red is ignored because theirs too many continuity errors(tommy fails to have his zeo powers a few years later in dinothunder)

<b>So is each member in action for like a year before retirement?</b>

The makers of the show always changes the cast for each new season. Usually what happens is the previous team loses their powers. Most teams dont reveal who they are. But yes most its a year.

<B>Anyone know the timeline??</b>

With the exception of spd, each season happens right after the other, give or take a few months. Wildforce was probably in action for the last few months of timeforec.

<b>And if the generations are that close from each other wouldn't it make sense for each new generation to have a leader or commander that was a ranger in the previous?</b>

It would make sense if the previous team revealed its identity and they were called together by a leader who could choose who to use. Generally in most cases, the powers are given to those by an external force(god or destiny).