TTB have a g.fast checker, but it's not for customers, only internal, partners and resellers.
It also throws up some weird results from time to time, it'll state a line can only have g.fast if an engineer attends but not available for self install or managed install.
That is most likely down to the 'grey area' that exists, whereby
they can't guarantee the g.fast speed due to border-line attenuation values, or suspected bridged-tap wiring.
An engineering visit will prove this, one way or the other.
