ExpressPCB switched to tin/lead process

[ezkcdude]

Hey, folks. I ordered some new boards this week, and immediately
noticed that they looked very shiny. Well, at first, I thought
something might be wrong, but upon further investigation I learned
that ExpressPCB has switched (back?) from a lead-free process to using
a tin/lead finish on their mini-boards. What does this mean? Well, not
much. Maybe easier soldering for the newer boards. However, more
importantly, while poking around the website, I found the following
note about storage of the lead-free vs. tin/lead boards (something I
had not thought about):

"Storage note: PCBs plated with a tin/lead solder finish can be stored
almost indefinitely before they are assembled. Our lead-free boards
also store well, but we recommend keeping them wrapped in plastic if
they will be stored for more than one month prior to being assembled."

So, if you have one of my boards already, it is the lead-free version.
Therefore, if you have not already built one, it seems that it is best
to keep it wrapped up (probably to avoid moisture). Also, if you have
built a board, get it cased up. I had noticed for a long time that my
old boards were getting kind of brown. I thought it may be due to
solder flux, but it was present even in my bare boards. I wish I had
known this before, but better late than never.