Source: aiccu Version: 20070115-17 Severity: serious SixXS will shutdown on 2017-06-06[1]. Unless there are other tunnel providers used with aiccu, it seems useless to include in stretch. >From a quick glance at [2], SixXS is the only provider using AYIYA and TIC which is what I believe aiccu implements.
Ansgar [1] <https://www.sixxs.net/sunset/> [2] <https://en.wikipedia.org/wiki/List_of_IPv6_tunnel_brokers>
