This is so that it fits better with how pkg version works.

What we have now is:

head 11.sYYYYMMDD + | | | 11.0.aX | | stable/11 +----------------+ 12.sYYYYMMDD | 11.0.bX | | | | | | | | | releng/11.0 | +---------+ | 11.0.pYYYYMMDD | 11.0.rX | | | | | | 11.0 | | 11.0sYYYYMMDD | | | | 11.0_X | | | | | | | | | v | | | 11.1.bX | | | | | releng/11.1 | +---------+ | 11.1.pYYYYMMDD | 11.1.rX | | | | | | 11.1 | | 11.1sYYYYMMDD | | | | 11.1_X | | | | | | | | | v | v v

On the head branch, we have:

- 11.sYYYYMMDD < 11.0.aX
- 11.0.ax < 12.sYYYYMMDD

On the stable branch, we have:

- 11.0.aX < 11.0.bX
- 11.0.bX < 11.0.pYYYYMMDD
- 11.0.pYYYYMMDD < 11.0sYYYYMMDD
- 11.0sYYYYMMDD < 11.1.bX

...

On the releng branch, we have:

- 11.0.bX < 11.0.rX
- 11.0.rX < 11.0
- 11.0 < 11.0_X

We also have 11.0(_X) < 11.0sYYYYMMDD so the release branch is before

the stable branch.