Sudden Loss Of Shifting Above 3rd Gear

Hey riders. Reaching out to see if if anyone has had a sudden loss of the ability to shift up beyond third gear.
Had not been having any issues prior to the event. Went for a short ride, made a stop for a milkshake, and on the way home stopped at a parking lot to do some slow speed maneuvers (basically all 1st gear with clutch and rear brake control), less than an hour, and on the way home found that I couldn't shift higher than 3rd gear. Shifting down and back up seemed fine and nothing seemed out of the ordinary, though the shift lever does travel a bit extra. My rear brake was noticeably soft.
Actions taken: Although clutch appeared to be in tolerance, I fine tuned it anyway which took the "slack" out the other end (where it enters the back of the case) - nothing changed or improved with shifting. Kick & toe shifter, and linkage are neither bent or damaged though do seem stiffer operationally than they were and are well protected by the full length foot board (only folds up so far and doesn't touch shifting components), engine and rear crash guards, and kickstand framework underneath. I say this because I did lose my balance once while stopped and positioning for next move and laid it down on the left side - guided. All was good as I continued maneuvers.

Replaced all brakes, since I was in maintenance mode. The rear brake fluid level went back up with the new pads but now have no range of movement in the peddle.

Unless I'm missing something, based on visual inspection and trying things under load (running while on stands) something seems off inside rather than outside and the lay down was just coincidental.

2012 T-Bird (28K+miles) original owner and all accessories are Triumph parts installed by the dealer at purchase.

Any thoughts, opinions, or suggestions will be appreciated. I'm willing to try things before hauling it to a dealer.

Thanks.

 

Thank you for your reply. Found out from a friend that some other triumph riders had a sudden shifting issue that they took to the dealer to fix. Unfortunately, the info didn't come with any details of the condition or bike models, etc. Thanks again!

 

North Yorkshire, fantastic. Nice country up there and went to York several times.

Thank you for your reply. Mine is a 2012 T-Bird. Found out from a friend that some other triumph riders had a sudden shifting issue (similar to your description) that they took to the dealer to fix. Unfortunately, the info didn't come with any details of the condition or bike models, etc. I'm mechanically inclined but this appears to be more than I'm willing to dig into myself. Thanks again!