This problem you mentioned is new to me - have not seen it before. Did you file a Github issue for this? Happy to chat more there (or feel free to ping me directly - ajay (at) timescale.com).
Just try to do a massive '\copy from' into a table that is already a timescaledb, using a tsv source with at least a few million records, make sure the dates are well spread out. Then use windowing functions to count the records per time unit. Compare date_trunc to time_bucket and select. Unless the issue was silently fixed, I'm sure you will be laughting too - but I recommend you wait until after xmas to have that good hearthy laugh, as it may cause you to want to fix the issue ASAP :)
Once of the field was defaulting to NOW(), maybe that's what caused the funny bug but I didn't investigate much after that. It was the straw that broke the camel back. Thousand papercuts. Not worth the time investment.