In reply to a post by Iniltous:

In reply to a post by PCJM40:

All the ONT manufactures have their own proprietary functionality for testing so a matching ONT and OLT is optimal.

Maybe so , but not in anyway necessary and certainly wouldn’t cause a catastrophic failure at a point in the near future,

Openreach had to pay Huawei for profiles to allow use of non-Huawei ONTs on their OLTs. Wasn't a thing that would just work, needed building of new profiles.

Certainly wouldn't cause imminent failure if there were a problem it just wouldn't work at all.