Rodinal has been my developer since 1978 and I still use it. After a couple of years of using whatever film I could afford, or that was available, I settled on a 125 asa film for my day camera and a 400asa film for my evening and night camera. I was taught proper developing by the b/w printer in Paris who I worked for. He got me to understand to judge the entire film and he got me to remember which grades of paper I needed mostly. Everything was about being precise with the temperatures, including the washing and about the agitation. He'd say: "the more you experiment, or change the parameters (film, developers, dilutions), the more you'll get lost".
Sorry for the length of the above, but it has to do with the answer to your question: just do a simple test shot of a well lit subject and develop, then print this. You should already get part of the answer when you look at the wet film after washing. The rest will become clear after printing. You will need to compare the result to your usual experience. If you generally end up using filter 3 (normal) and now you need filter 5, that would be alarming to me.
Yes, Rodinal can be fine after many years. But also not when kept in, for instance, very hot temperatures.