README: correct opentopia count, note seen-ring is RAM-only, site-neutral LED wording

README.md

@@ -108,7 +108,7 @@ it stays out of the way. The CC1101 board's BQ27220 gauge is not supported.
 | blue dot running round | connecting to a camera |
 | teal, draining | countdown to the next camera |
 | amber, steady | paused |
-| red blinking | camera offline / insecam unreachable, skipping |
+| red blinking | camera offline / site unreachable, skipping |
 | dim grey | menu open |
 
 ## How it works
@@ -116,9 +116,9 @@ it stays out of the way. The CC1101 board's BQ27220 gauge is not supported.
 * `insecam.c` fetches one listing page (`/en/byrating/` or `/en/bynew/`, random
   page) — six cameras per request, so insecam sees one hit every two minutes.
   insecam's whole catalogue is only ~1,700 cameras (287 pages × 6) and
-  opentopia's rated list ~3,000, so Random keeps a ring of the last 1,200
-  cameras shown and skips them; without it the birthday effect makes repeats
-  common within an hour.
+  opentopia's rated list ~2,000, so Random keeps a ring of the last 1,200
+  cameras shown (in RAM, cleared on power-off) and skips them; without it the
+  birthday effect makes repeats common within an hour.
 * `opentopia.c` does the same for opentopia (`hiddencam.php`, rated or newest),
   then, just before a camera plays, reads its page in *Live Feed* mode for the
   camera's own MJPEG URL (or *Current Still* when there is no video). The site is