How can I debug whether SC incorrectly removes a tag?

[burrscurr]

Way 152370702 was tagged cycleway=opposite + oneway=yes. Apparently, via a SC(EE) resurvey of the cycleway in changeset 162139648, this was changed to cycleway:both=separate. However, since the (deprecated) cycleway opposite family implies oneway:bicycle=no – shouldn't SC add this tag when replacing cycleway=opposite with regular cycleway tagging to avoid information loss? (See mapillary for pretty recent image confirming oneway:bicycle=no.)

How can I debug whether this was user error or is an issue with SC or SCEE?

[Helium314]

I think the assumption with cycleway:both=separate is that you have to cycle on the separatly mapped cycleway if you want to go against the oneway. Then I don't think the road should be tagged with oneway:bicycle=no.
The road you linked doesn't even have a separate cycleway for about half the length, so in my understanding this case is a user error (should have split).

But in general if you are allowed to go against the oneway on the road, but there is also a separate cycleway, wrong tagging might be done by SC. If such situations actually exist, SC would need to offer a separate and may use the road in both directions option.

[westnordost]

The user answered that there is a bike path (in the opposite direction to the oneway flow), but it is displayed separately on the map. (Which seems to be wrong, i.e. a user mistake.)