@bortzmeyer @winfried @jpmens @bert_hubert @woody Some consequences of this lag:
$ dig +short @c.root-servers.net int DS
27433 7 2 <...>
$ dig +short @a.root-servers.net int DS
59895 13 2 <...>
27433 7 2 <...>
(Change spotted thanks to @diffroot: https://mastodns.net/@diffroot/112481363668615396 )