Alma
For print titles updated by pocket parts and disposable supplements, we only include item records for the permanent, bound volumes in Alma.
So, under the holdings record for the title, there will be items for volume 1, volume 2, volume 2A, etc.... Any volume that is hard-bound and forms a permanent part of the title.
See screenshot attached to this page. (Note that newer volumes will have barcodes.)
We do not create item records for pocket parts.
Keeping track
But, of course we want to keep track of what we paid for and what we've received. So we use a spreadsheet in Google Drive to record the receipt of pocket parts.
Print materials with pocket parts are such a small part of our collection now that it doesn't matter very much how we handle these. But there is an alternative as discussed on ALMA-L, and I'll write it down below.
Alma alternative
Create a separate, suppressed holdings record to check the loose-leaf or pocket part updates into.
This allows the library to maintain a record of receipt but not have the individual updates appear in the online catalog.
1. Create a second holdings record for the title but suppress it.
Everything can be the same as the original holdings record, except put |m pocket parts or |m loose-leaf updates after the call number, like this:
852 0_ |b MAIN |c uref |h KFR57 |i .W4 |m pocket parts
2. Suppress the record in the MD Editor by going to Tools > Set Management Tags > Suppress from Discovery.
Then File > Save and Release Record.
3. Create item records for individual pocket parts, disposable supplements, or loose-leaf packets as they arrive, per normal procedures.
Ideally, remember to withdraw item records for pocket parts and supplements that are discarded after having been superseded by newer editions.