Ok you lovely bra-fitting angels... I've measured myself, now please come and tell me my true size

[justkeeponsmiling]

Ok, so following a previous post where I was asking for help to find a well fitting size 38A bra, I have followed all the advice and tried measuring myself today..
It seems I measure 30.5 inches underneath my boobs and 33.5 inches when I lean forward and measure across the biggest part.
Please could anyone advise me which size I should try, and if it should be roughly that size in every shop?
Any help greatly appreciated! :)

I'm not an expert, but I think I remember the threads saying:

Under ribcage - actual size. So you'd be a 30/32.

Cup size, 1 letter for each inch difference. So you'd either be a 30C or a 32B.

No expert either but love love love these amazing bra threads would agree with ligule 30c
The actual experts are never far away
Be aware that a 30 back will feel v different at first if you have been in a 38

Sorry lougle not ligule.