So during the Principate would it have been feasible or economical for the province of Britannia to be divided either during the completion of the Antonine wall (or an analogous wall in the same location if Hadrian felt a bit bolder than OTL or someone else got the throne?). I'm thinking the Advantages would be that two of the three legions stationed in Britain were in the south to dissuade any revolts and to guard against Hibernian pirates so no single proconsul or propraetor would have access to three whole legions and Auxilia (though there is the possibility any two governors could ally with one another in betraying the emperor it still would be a nice precaution), and another would be it would be far easier to hold the area between the two walls with a proconsul handling the situation from Eboracum rather than from Deva or Camulodunum.
Now if it did happen what would the best positions for it be in the case of just the Antonine walls as opposed to a timeline where (most) of Caledonia is Pacified with the lowlands and Eastern coast firmly under Roman Rule and client chiefdoms in the highlands.
Now if it did happen what would the best positions for it be in the case of just the Antonine walls as opposed to a timeline where (most) of Caledonia is Pacified with the lowlands and Eastern coast firmly under Roman Rule and client chiefdoms in the highlands.