Missing 30° in extension and can only get into flexion about 90°.
Not an acute injury it came up over a couple days, it seems to respond to trigger point/mobility in the rhomboid area.
I made a fair amount of progress in extension and the other day training it got forced into a little more flexion then it wanted. The next day I was missing 25 to 30° of extension and today I could only get about 90° of flexion at the elbow.
Rolled it, smashed it, scrubbed it, and blasted it with a percussion gun all in the rhomboid area and that has given me a little bit more ROM.
All my healthcare providers are mystified
Would definitely modify current training to be sure not to further aggravate it and if you continue to notice loss of ROM and are no longer seeing progress with rolling, smashing, percussion gun etc. I would continue to seek out a physio or healthcare provider so that you can address the issue properly.