They're guaranteed to hit their 2019 overall max when the factor reaches 100%. Glu could go over that, but it's not a definite.
@tshea510 - correct - ATGs from 2019 are not special or unique in any way in 2020. All keepers, whether they're legends or ATGs will have a standard "keeper factor" ratio applied to their 2019 base rating. This is the reason why so many guys have taken regular legends like Cruz, Brett, Bench, etc. as their keepers - ATGs simply aren't special. At the moment the "keeper factor" is at 0.48, so a 600 max guy in 2019 is currently a 288 max in 2020.
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