In the profile reporting under [CertificateKeyAlgorithm_ECC-nistP384]
https://profiles.opcfoundation.org/conformanceunit/2444

I see this:
"The P-384 or P-521 curve described in http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf.
ECC public key compression is not used.
ECC coordinates are encoded as big-endian integers padded with zeros.
Signatures and keys are 96 bytes or 128 bytes."

But it is complete nonsense to say that Signatures or keys of nistP521 are 128 Bytes,
because they are (521+7)/8 * 2 = 132 raw bytes.
However it is completely misleading to point that out, because the ECC_nistP384 protocol
is not expected to use raw ECDSA signatures, or ephemeral keys of that type,
if they are used those are DER-encoded signatures embedded in a certificate.