You might be thinking about a Photonic Bridge Officer. If you type Photonic under the Bridge Office section you should find some there - assuming any are for sale. It might be Photonic on the DOFF system name too.
There are a few that exist on Holodeck. Some players were lucky enough to catch some that slipped through the cracks (critical sucess results science cadre recruitment, asylum, etc.) I think those cracks are sealed now though.
There is no real use for them though as far as doff missions go until they are released. I sent mine out on the one mission that comes up once in a while.
However the crew recovery rate inscreased by 75% could be handy.
I will be checking into the pipeline today the reintroduction of EMHs. Note it will take a while before it makes its way to Holodeck, however.
Will there be "instructions" on how this new/revamped system will work? I understand it has something to do with purchasing the EMHs via EC, is that right? And that there are other Emergency X Holograms, not just Medical, right? Will these be purchased from Ferra (and the KDF equivalent Gorn dude) or elsewhere?