1. PON authentication may require serial number + password. If the ISP won't change the serial number for you, your ONU must support changing the serial number. Until Ubiquity publish the documentation about this, don't bother about it.

2. If you are using Huawei, you might want to try the default superadmin (telecomadmin) account. I managed to login to it last year on but later Time has updated the configuration remotely & changed the password. For Time, the password is same as the PPPoE password if I remember correctly. You can try the following steps at your own risk
https://zedt.eu/tech/hardware/obtaining-adm...huawei-hg8247h/

3. Don't bother about SFP ONU. The configuration can only be pushed from the OLT provisioning. It is meant more for service provider or corporate user. I doubt your ISP will even entertain you if you are just home or low tier business subscriber. I have a gpon onu sfp module collecting dust because of this.

I agree, its 2020. Quite a few brands are now cheap and reliable these days. About the ufiber nano/loco, i doubt it will work with our isp. Tho it did entice me.