Dynasty. Have Lacy/Gio/ellngtn and TY/Odell/JohnBrown/Garcon/Wright. was just offered Jamaal Charles for OBeckham? Keep w/beckham for years to come, Charles nearing the end?
OBJ is gold in Dynasty. It would take LeVeon Bell or Antonio Brown probably to pry away OBJ in a dynasty format. I wouldn't do it for Charles, unless there are contracts involved that make money a factor.
IF it is Dynasty, I would keep Beckham. Charles has 3 years left , if not 2 years. Beckham will have at least 6-8 years of WR1 life left in my opinion. WR has a longer lifespan than RB in general.