I wanted to provide a simple answer but later found that I don't know it.
However, I do recall there were a couple of sites dedicated to this game, many years ago. Here's one of it and has what's closest to an answer.
"Hereafter, a Senator may govern one or more Provinces through a Legate while remaining in Rome in some other office or commanding an Army in the field."
The above is the original text of the card. It opens up a Pandora's Box of questions that need answering. The following is my interpretation of how the card should work. These rules were written with PBEM games in mind.
1. An aligned Senator can be Governor of more than one Province at the same time. An unaligned Senator can be Governor of only one Province at the same time.
2. A Senator must be in Rome to be proposed for a Governorship. He can be proposed for multiple Governorships in the same or different proposals. He can be proposed for a Governorship even if he currently holds another Office.
3. A Governor can only reside in one Province at any one time. A Governor may also opt to reside in none of his Provinces. A Governor may not reside in any of his Provinces if he currently holds an Office other than a Governorship.
4. When a Senator is elected to a Governorship he has the option either to reside in a Province he has just been assigned to govern or to stay in Rome. He must stay in Rome if he holds an Office other than a Governorship. An unaligned Senator will always reside in his Province.
5. A Governor can leave Rome to reside in one of his Provinces at any time during the Senate Phase after Prosecutions have been held - unless he holds an Office other than a Governorship. A Governor cannot travel between his Provinces.
6. A Governor may return to Rome from a Province only at the end of the Revenue Phase. A Governor must return to Rome at this time if the term for the Province he is currently residing in just ended.
7. A Province whose Governor is currently not residing in it is said to be ruled by Legate.
8. A Corrupt Governor can only be Prosecuted and/or fined via Calpurnian Law on the turn that his Governorship ends. He may be Prosecuted and/or fined once for each Province from which he collected Personal Income. It's possible for a Governor to avoid Prosecution by staying away from Rome in one of his other Provinces.
9. Note that via the Recall rule (9.622), a Governor can be stripped of his Province before his Term expires by having a new Governor elected in his place. Since Governor Recalls occur after Prosecutions, a Corrupt Governor thus recalled will avoid Prosecution; though he can still be fined.
Why was Living rules was different from Valley Games 1.04: Valley Games made a couple of changes to the rules back then.