Matt, Thanks for the TZ.lua Github link. Though I found that page was not presented in the format I'm used to on Github. ALL the files on that page appear to be in HTML format rather than what they purport to be, making it hard to use. I managed to convert the .lua and .md files to real code and formatted text (resp.), but the .zone files elude me. Not that I'd use them (as you suggested I don't), but I just wanted to view their structure. But even renaming one as .html, it did crazy things in both Firefox and IE, and would not display the contents in any form I could recognise. I also tried downloading the 'raw' version, but it was not ASCII text. I am aware that there are 'derivative' versions of the TZdb. But after many decades of experience, I have little faith in the longevity of any specific website. And I would have less faith in a site established/maintained by just one person/tiny company than I would in one maintained/sponsored by a large organisation (like the TZdb is). Remember I'm talking about a hardware product, which I would hope might have a 20-30 year lifetime (though with the low-cost Chinese-manufactured NodeMCU, that might be wishful thinking!), and I don't want to have to be sending firmware updates to users whenever a requisite website disappears. Regards, Daniel