They ain't gonna happen. IntSys prefers to add new TT units in before rerunning old ones. Tobin still hasn't been reran, the only one who was reran (twice) was M!Marth and even then it hasn't been done again since Christmas.
Obviously they can't be in an easy rotation like GHB units so really I think they should just be added to the summoning pool (barring LA!Eliwood and NY!Corrin for being seasonals, but add them to seasonal/legendary banners). Now they don't need to be reran and now some of the nice fodder enters the normal pool AND everyone would benefit from IVs, which is nice to have if literally every meta unit (barring some really good F2P units like BK) and the fact Kaze jumped up a tier due to being added to the pool
They should just be added into the pool at some point. I don't see why they need to keep certain units with neutral IVs. These TT units have neutral IVs because they're an in-game reward, much like the daily rotation maps and freebies like the chosen CYL, L!Ike and Takumi.
Well, let's consider a couple things. Marcina was rerun due to the Tempest Mini. They could still do a Tempest Mini ver 2 if they prefer.
However, what I find more interesting is the recent "4 Heroes" maps they did, rerunning a Grand Conquest only unit Kaze. That says to me that there could be reruns for those Tempest exclusive units via special map events or even through Grand Conquest prizes.
Furthermore, we may see certain units rerun on the 1 year anniversary of their first appearance. Though I do not remember if it has been a year since Tobin was released.
Next we can also count Black Knight as having been rerun due to appearing in a promotional orb package, event though it was "for purchase" it is still far cheaper than trying to summon a specific unit.
I think people will need to start requesting those units more frequently too. So, I wouldn't rule their future appearance out completely, but player demand and event opportunity to maintain player interest/purchases will play a part in IS's decision making process.
I'll keep my finger crossed because I missed out on several units too that I would like to claim.
I would suggest periodically filling out customer feedback inside the app requesting reruns of Tempest units.
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