250mg great gains can be made, is pretty much 2x natural test levels. 99% chance you won't need an AI at this dose and can give you boost while getting back into the swing of things
Don't think about it as a race to the finish line, you can always do another cycle if you need too. I would go from between 250-350mg If I was you.
I dont like doing anything less than 16 weeks. After 4 weeks if you feel good no sides bump it up by 50mgs and so on and so forth
That way you have a good starting point for any future cycles because it really is never just one