I just saw the grim news: F 1,2, Tactics removed from catalog.
Apparently, from 2014, GOG isn't holding the rights for distribution of those three legendary games any more, so they had to close down the shop. The rights were managed with old franchise owner, Interplay, and current one, Bethesda, didn't bother to renew them. Yet. It's the beginning of the year, so things can change, hopefully.
Those who snatched the games on that recent promo giveaway can keep them, but no one can buy new copies, nor are gift codes from the promo valid (earlier gift codes that were actually bought are still valid).
That's a hard blow to the history of gaming and legacy-buffs. GOG versions were as polished and accessible install-vise on modern machines as possible, so young generations will have hard(er) time if they want to experience the original post-apocalyptic deal and feel.
I'm glad I at least finally got all 3 of them in the promo sale.