Generation an accession number in 852$$h or $$j can only be done by using the menu (Tools -> MARC21 holdings -> generate accession number), or by keyboard shortcut (ctrl+schift+A) in the new MDE.
Even though the keyboard shortcut saves some clicks, we would like to type the prefix directly in field 852, followed by a character like # for example, that would indicate to Alma to generate the sequence number after saving the holding record.

Example : 852 $$b library $$c location $$h RIA #
-> after saving the record :
852 $$b library $$c location $$h RIA 6785

If the prefix doesn't exist in the accession number code table, there should be a warning upon saving.

Also, it would be helpful if the accession number does not need to be connected to a specific location. We should be able to choose to connect it to all locations of a library, or only one location like currently.

Best regards.