Really not much change. Seems pretty baseline behavior although clearly still doesn't want to jump. I think the mass is growing so mostly suspect it's a tumor or malignancy. She's definitely not laying and around here that's a requirement (for chickens). I'll necropsy in about a week and post...
I thought maybe the stimulation of the exam could help with passage but looking at your diagram I am now guessing this isn't a egg bound chicken. The mass would be dorsal or immediately cranial to the vent and everything I've read suggests the egg should be readily apparent with examination...
Yes palpable maybe 2cm ventral (towards chest) to the vent. Feels large and firm enough to be an egg. Definitely not far enough anterior to be the gizzard.
Internal laying is an interesting idea but I wouldn't expect it to represent a large firm palpable mass in that case.
If she doesn't lay...
Hen is a 2.5 yr old RIR. Excellent layer and good body weight at baseline. About a week ago she tried to sleep in the egg box would not jump up to roost, then wouldn't jump up into coop (elevated coop, don't use a ladder). These are never issues for her. Isolated her and she's not laying...