Not sure if this is an r/askhistorians -quality answer, since it's not actually based on my own knowledge, but you will likely be interested in ORBIS, a collaboration between the information tech and history departments at Stanford: https://orbis.stanford.edu It can answer this and all sort of other similar questions about Roman travel time and cost, adjusted for all of the kinds of variables you would need to think about when planning that kind of journey: whether you're on foot or have access to animals or vehicles (faster, but expensive to feed), the season, what kinds of boats and waterways you have access to, etc. So between Berenice and Deva, it's easy to fiddle with the variables and get anywhere from two months to nearly a year.