[tlbuild] tl20 pre-pre-builds

[Karl Berry]

    Just out of curiosity: do we plan to attempt using ICU 66 for TL20 

No. (BTW, I already wrote about this when Nelson mentioned the ICU
release schedule some time ago.)

    and ICU 66 is just an RC

Not interested in using an RC.

    At least they recently fixed a Solaris-related bug I reported to them,
    so I there's a chance we could remove some patches.

But since the patches are ok, this doesn't seem especially necessary.

I will update ICU at some point during the year.

Unless ICU's release schedule changes, we will generally be using one
release older than the "current" one. I don't see this as a problem. If
there is some critical feature or bug fix in the current one some year,
we can address it then. --best, karl.