I read it a couple of years ago actually but I cannot recall any reference to a DLM reset, so as you have read it more recently then point me to the page or are you just assuming again?
Perhaps you have a misunderstanding of the initialisation stage.
"From G998.4, with G.Inp enabled without support from the modem, initiallization failure will occur. I.e the modem will be unable to connect and therefore be unable to update the firmware. Catch22. Unless, as I posited earlier, a DLM reset removes G.Inp to allow the upgrade."
Is that your assertion (in bold)? Where does it state a DLM reset is necessary? I certainly don't recall it.
DLM cannot remove G.inp as it has no control over it. G.inp will only be recognised by modems that support it, those that don't will automatically get an update to be able to initialise with it providing the ISP management system can make changes to the modem which (getting back to your original question) will not be possible with 3rd party modems.
Note: Openreach modems ECI or Huwai will be updated as required as they are still in use.
DLM cannot remove G.inp as it has no control over it.
Then Fastpath couldn't be enabled.
I see you've missed the point completely again.
"To further muddy the waters, G998.4 para 11.1.13 has a configurable parameter which allows for either forced activation regardless of capability of the units or preferred activation where it is only activated if supported"
That is a configurable parameter, it doesn't mean it's been configured that way.
Even if the activation was forced if the modem does not support it then the modem would reject it.
I imagine that Openreach will use the forced activation so that those modems that don't support it willl get the relevant update otherwise how can "Those currently with non-Retransmission compliant modem firmware will be identified by management systems and updated, after which Retransmission will become available" be idenitfied? Preferred activation would only happen on modems that support it.
So you still haven't identified or shown where a DLM reset must be performed.
When you eventually come out with some sensible proof for your assertion I may come back for further discussion but get you facts right first and some knowledge of what you want to discuss.
Meanwhile, I'll leave you with this.
There is no evidence that implementation of G.Inp will necessitate a DLM reset, those BT or Openreach modems that do not support it will be automatically updated to do so. 3rd party modems may already support G.Inp but if not would need a firmware upgrade from the OEM.
Unless of course someone can prove otherwise...
I think everyone is missing the point of what G.Inp is there for. It won't effect Fastpath or DLM. It is merely for between cab and modem when SHINE causes a loss in transmission. The data exchange between modem and can at c4ms for the retransmission request would not invoke DLM intervention.
It is seen as a precurser to vectoring deployment and eventually G.Inp, DLM and vectoring will work side by side, with none interfering with the other.