AT&T lte to lte-a changing

I have a pepwave transit cat 18. With my AT&T plan I see the connection switch from lte to lte-a quite a bit. My other plans, Verizon and calyx, once they connect to lte-a they pretty much stay there. I have seen the att plan change multiple times over the course of a few minutes. Is this normal?

this is normal for ATT, LTE-A is only displayed when CA (carrier aggregation) is in effect, and is only in effect while pulling data.

OK, sounds good. Thanks for your response.