If you have the required settlements and have started the script every time then check Rome to see if a new building has popped into place called Polybian Era (or something like that). This new building will allow you to upgrade your barracks to give you polybian troops. If this building doesn't exist in Rome then either you have been editing EBBS or you haven't loaded the script a couple of times by accident. If the former then you will need to put in the original version of the script, if the later you need to play on for a couple more years and hope that something pops up.

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