Will John Carlson Keep #74?

i know the capitals are in need of goons like john erskine, who wears number 4, but i have a feeling they will release him next year when his contract ends. Joh carlson currently wears #74 but when playing in juniors and for the AHL Hershey bears he wears #4. Im planning on buying a john Carlson jersey this year and dont wanna waste $180 if he goes back to #4 next year. So do you think he will stick with #74?