It appears the parsoid apt repo https://releases.wikimedia.org/debian/dists/jessie-mediawiki/ was rolled back to older timestamps (deb https://releases.wikimedia.org/debian jessie-mediawiki main)
Anyone who updated prior to the rollback will not be able to update to parsoid 0.11.0
```
$ sudo apt update
...
Hit:3 https://releases.wikimedia.org/debian jessie-mediawiki InRelease
...
$ apt-cache madison parsoid
parsoid | 0.10.0all | https://releases.wikimedia.org/debian jessie-mediawiki/main amd64 Packages
parsoid | 0.10.0all | https://releases.wikimedia.org/debian jessie-mediawiki/main i386 Packages
```
Workaround:
```
$ sudo rm /var/lib/apt/lists/releases.wikimedia.org_debian_dists_jessie-mediawiki*
$ sudo apt-get update
...
Get:42 https://releases.wikimedia.org/debian jessie-mediawiki/main i386 Packages [504 B]
Get:43 https://releases.wikimedia.org/debian jessie-mediawiki/main amd64 Packages [504 B]
$ apt-cache madison parsoid
parsoid | 0.11.0all | https://releases.wikimedia.org/debian jessie-mediawiki/main amd64 Packages
parsoid | 0.11.0all | https://releases.wikimedia.org/debian jessie-mediawiki/main i386 Packages
...
```
Fix: Please update the apt repo with new build.