I've build the ROM for SM-T580 (gtaxlwifi) from source:
- LOS Updates 2018-03-20
- Security patch level should be 2018-03-05
I'm not owner of such a device, so I don't know what is working.
Download is available on AndroidFileHost.com (search "gtaxlwifi").
I'll try it asap, thanks
Works very well!