Marc21 field 490, "series-statement", and Marc21 field 830, "series-uniform-title", are available on the Order List Letter (letter code: OrderListLetter).

However, the content is not complete :-(
Only 490|a goes to <series_statement>, 490|v - the Volume is missing.
Also 830 only provides |w as <series_uniform_title>, |v is missing.

Please see example:
035 __ |a AC04654069
245 00 |a Keiner wird gewinnen |b populäre Musik im Wettbewerb |c Dietrich Helms ... (Hg.)
490 1_ |a Beiträge zur Popularmusikforschung |v 33
830 _0 |w (AT-OBV)AC00913498 |v 33 |9 O:1

<series_statement>Beiträge zur Popularmusikforschung</series_statement>
<series_uniform_title>(AT-OBV)AC00913498</series_uniform_title>

Please add 490 subfield v to the XML field <series_statement>, e.g. separated with semicolon:
<series_statement>Beiträge zur Popularmusikforschung ; 33</series_statement>

Not important for our library but maybe for other libraries: please also include 830 subfield v to the XML field <series_uniform_title>.

Thank you in advance!