The Zwift TT events have always used A-D categories (apart from a small period of time where they used ZRS.
I felt that as TTs are less about who you beat and more about holding steady power, A-D power based categories made more sense.
What about the event description did you find confusing / misleading?
The event description says the categories (A-D) are based on W/kg. From the explanations on this thread, that’s not the complete story.
It’s based on what your zFTP is in w/kg (or in some scenarios what you zMAP is but largely zFTP).
What you have said is correct, but I would prefer to not over complicate it. It is not common for category to be set by zMAP and when that does happen (imo) the rider would probably be capable of getting their zFTP to be at that level of category.
Week 2 of the 4x4 TT series starts at 1720BST today, in ~45mins.
~19Km, Going Coastal.
That’s not the topic of this thread.
James, thanks for the info.
I’m not sure of the relevance / purpose of this post 
The US CST and EST is apparently not the target audience for this event. I thought there would be some rotation through the week but there is just a void every day. Seems like at least TT club could be more often since attendance isn’t an issue.
EDT here. Have a fortuitous gap in my work schedule tomorrow for the 2:20 slot.. but you’re right. It’s that or 7:20 which is no good with younger kids.
I don’t think I’ve ever seen the Zwift TT Club monthly series ever be so popular, ~40 in pen D at 1720BST on Monday and 50+ signups at similar time yesterday…
Usually a good turnout in D is 10-15 racers! 
About a 300% increase weekly vs last month.
Amazing what publicity will do.
