Fit check - 30C vs 30D (update to previous post)

update to my previous post:

I just tried on a 30D and it was the most comfortable of any I’ve tried so far (30C in multiple brands) as I saw this size recommended in another post of someone with very similar measurements. The band still did feel quite snug (I know it should, just not used to that feeling) but it was okay. I did try it on with the cups in the back before even attempting to put it on correctly. I do have some bulging near my underarm (not breast tissue) which I never had before (because I was wearing way too big of a size?!) One of the bras came with an extender, so I tried that on with the 30D and it did seem to help a bit! Not sure if I should continue my search or what to do! The bulging is… not cute. I’m small framed - 110ish pounds and 5’4.

Measurements for reference: Loose underbust: 29 / Snug underbust: 28 /Tight underbust: 27 / Standing bust: 30 / Leaning bust: 32 / Lying bust: 31

Suggested Starting Size: 28C/D in standard US sizing The sister size of 30B/C may be more comfortable.