I had a small issue of a broken C6 in 2011, also clavicle, compression/slippage C5-C6-C7, Long Thoracic Nerve injury, right shoulder needed replacement all adding up to a limited range of motion once crash was healed. To improve motion I would sit down in our long shower stall or tub when elsewhere with HOT water hitting back, extend right leg straight out-cross left leg while bending at knee over right leg-keep left foot against right leg, slowly twist right at waist and neck as if to look back while pushing with left hand on floor at right hip and left hand on floor behind to left side providing stability. Hold a bit and reverse. HOT water helps relax and in time my range of motion increased a lot. I do this after every ride and every night when I shower. Takes a few minutes so no problem finding the time. I follow twist stretch with forward bend at hips as far as possible.

This Sunday I have the 167+ mile One Day Cross Florida ride and will take a HOT shower about an hour before starting and include the stretching. Also a LONG STRETCH after the ride.