I don't know if this has already been reported, but it's annoying enough to insist.

It happens to me in SP games since the 1.03 patch.

I setup a game with the LOCKED TEAMS option and ally with one comp.

The game then starts OK : if I press F1, I can see that the chosen comp & I are locked allies (no changes possible), and the other (enemy) comps do not try to contact me.

But ... if I reload a save from that game, the teams become unlocked, and I start receiving mission offers from all the comps !?!

If I then press F1, I can see that my ally is at 100% satisfaction ... but if I don't accomplish his missions, that % goes down and he eventually breaks the alliance and becomes my enemy !

Since my strategy had been planned in the context of having this ally locked from start to finish, now having him as an enemy can be a major annoyance.

Why does loading a save break the locked-teams options ? Is it a bug ?

I think so : if I chose "locked teams" as a game setup option, I meant it. The reloaded saved game should respect the state of the game's options when it was initially setup AND at the moment it was saved !