Is AGPL Compatible with GPL for the purposes of BSL License Change

Question

I would like to license two products, one with AGPL, one with GPL.

The requirement we have is that we want to keep the initial release until BSL, but thereafter OSS is fine.

I believe the most compatible license with our intention is MariaDB's BSL (Business Source License 1.1).. https://mariadb.com/bsl-faq-mariadb/

Three main "in the wild" usages are Sentry, CockroachDB and MariaDB. Each have written articles about the usage.

• CockroachDB: Blog then License
• Sentry: Blog then License
• MariaDB: Blog https://github.com/cockroachdb/cockroach/blob/master/licenses/BSL.txt

What I would simply like to know is, the BSL license requires release under a GPL compatible license, but I cannot find a definitive answer if AGPL is compatible. The Affero General Public License Wiki provides that

In the Free Software Foundation's judgment, the added requirement in section 2(d) of Affero GPL v1 made it incompatible with the otherwise nearly identical GPLv2. That is to say, one cannot distribute a single work formed by combining components covered by each license

This causes me confusion... in one vein it says compatible another incompatible.

Answer 1

The final quote you include correctly states that the AGPLv1 is incompatible with the GPLv2. However, the AGPLv3 is compatible with the GPLv3.

The BSL's requirement of GPL compatibility is

“compatible” means that software provided under the Change License can be included in a program with software provided under GPL Version 2.0 or a later version

I read this to mean a Change License's compatibility with the GPLv3 alone is sufficient, especially since several BSL grants name the Apache 2 License as the Change License, which is only GPLv3-compatible.