Yes, but you need ssh access to coccia, i.e. be a DD. Looking on there at
dak|ignition-math2_2.9.0+ dfsg1-1_source.changes|Error while loading changes: No valid signature found. (GPG exited with status code 0)
> gpg: Signature made Tue Jan 9 22:50:01 2018 UTC
> gpg: using RSA key A08161BBEC1CC063961459035E946C
> gpg: issuer "email@example.com"
> gpg: Good signature from "Jose Luis Rivero <firstname.lastname@example.org>" [expired]
> gpg: WARNING: Using untrusted key!
Your key has expired, or at least the copy in the keyring. Note that the
keyring is uploaded manually around once a month, so even if you renew your key
and upload it to the keyservers, you won't be able to upload anything for a
while and will need sponsorship.