diff --git a/2022/vcfb2022-octoi/octoi.adoc b/2022/vcfb2022-octoi/octoi.adoc
index a7699c9..3649fc6 100644
--- a/2022/vcfb2022-octoi/octoi.adoc
+++ b/2022/vcfb2022-octoi/octoi.adoc
@@ -54,7 +54,7 @@ OCTOI - Osmocom Community TDM over IP
 == History: ISDN + digitization of subscriber line
 
 * German national ISDN (1TR6)
-** available publicly from 1992
+** available publicly from 1988
 * Euro-ISDN (EDSS1)
 ** MoU signed in 1993
 ** widely available by software update of exchange switches in 1994
diff --git a/2022/vcfb2022-octoi/octoi.html b/2022/vcfb2022-octoi/octoi.html
index 0b6e361..05038ab 100644
--- a/2022/vcfb2022-octoi/octoi.html
+++ b/2022/vcfb2022-octoi/octoi.html
@@ -4021,7 +4021,7 @@ German national ISDN (1TR6)
 <ul class="">
 <li>
 <span>
-available publicly from 1992
+available publicly from 1988
 </span>
 </li>
 </ul>