Strange Lump On Hen

[StarryOne1998]

So one of my chickens has a weird lump on her chest. I'm not entirely sure what breed she is, I just know that she is this georgous light orange with a darker neck/head/tail and some black on her tail. Anyways, she is about 2 years old now.
I noticed, right around when she turned one, that she had a weird lump on her chest. She kept readjusting it the way I had heard chickens will readjust their crops, so I thought she had just eaten a lot of good stuff that day. But this lump keeps getting bigger and bigger, and is bothering her more and more. She is "readjusting" it almost constantly now, and if I am close enough I sometimes hear it make this weird squishy noise. The few times I felt it, to see if I could do anything, it felt squishy like a crop. My mom thought it was her crop at first too, now she thinks it might be an air pocket or bit of fat, if that is possible. But I am wondering if it might by a cyst? If someone could answer, that would be great. I'm going to try to get some pictures up too.

 

[StarryOne1998]

Here are some pictures of her. The top one is one that my mom took right around when we first really noticed it and thought that something might be wrong, and the other two are from early March. If I don't figure out what is going on with her and it isn't fixable, we may have to cull her soon. It is messing with her quality of life.

 

[chickenprince55]

My chicken had something similar for about a month that I kept thinking was a sour or swollen crop and I read to hold them upside down so I did that twice a day for like ten seconds and eventually it went away .