Auto Conversion 16-bit to 8-bit?

I think I'm loosing my mind. I'm opening NEF files in Photoshop CS, editing them and saving them as PSDs or JPGs. I often save first as PSD, then convert to JPG. Up until 2 days ago, I did not worry about converting the images from 16-bit color to 8-bit color. Now, the save as JPG option is not available. DON'T YELL AT ME YET! I know you cannot save a 16-bit file as JPG. I checked files I converted last week....the NEFs were 16-bit and the resulting JPGs were 8-bit. My issue is, last week, I swear, I didn't convert from 16 to 8. It somehow, was happening behind the scenes(magic?). This week, I have to manually change from 16 to 8 and I don't understand what could be different.
Additional info. The only thing that has happened, is that I installed TRIAL Nikon Capture 4.2 over an existing TRIAL Nikon Capture 4.1. I've since, uninstalled Capture, I've uninstalled PhotoshopCS and reinstalled. I also have Nikon Picture Project 1.1 on my XP machine.
Any ideas what has caused the difference??
Thanks,
Bill

William,

Its been working this way as long as I can remember. If you use Image Ready (save for web) to save the JPGs it’s all taken care of.

If you just “Save As” you need flattened, 8-bit, no paths or alpha channels, etc. Since you should also convert to sRGB, I use an action.

There is no relationship to NC or any other packages I can think of.

Cheers, Rags :-)