^ Possible!
Without any stats from the MT992 we are working blind.
Also there is the possibility that DLM could have changed something which affects the sync speed. I'm not sure if recent FTTC DLM amendments also follow over to g.fast or not, as g.fast wasn't mentioned.
So I suppose there is a chance that the line was on full open profile when the engineer performed his tests but after a day the default DLM profile has kicked in - whatever that is for g.fast? It was last year when the engineer ran tests on my daughters line but I know he reset DLM to Open yet a few days later they had interleaving applied.
You may be able to spot interleaving based on latency - however that could depend where you live and which Zen gateway you are going through.
If you are on their Manchester PoP and live down South it could be harder to tell. With my daughter living up north, being on their Manchester PoP makes no difference to their overall latency.
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PS - For clarification:
Zen are seeing you sync at 236737.
229151 is your IPprofile
TR101 basically just means Ethernet backhaul (21CN WBC/WMBC).
Interleave Auto - means can be on or off as dictated by DLM. This is historic from the days of ADSL as it can't be set as off when on VDSL
You many be able to get Zen to give you your DLM profile if they run a GEA test - although it does sometimes lag behind by 2 weeks.