Ume Boshi with wild plums

I just tried this for the first time in vacuum bags. After about a week the bag was full of gas I then moved them to a jar with a bit more water to cover the plums. So delicious I don't think I'll be able to leave any to dry out. But the juice is so good. Hope it gets to be a vinegar of I can stop using them.

Another failure, in case it's of use:
I had a lot of fallen green apricots this year.
I put them in a small sauerkraut crock with salt.
They made just enough umesu to cover them.
By this time the shiso was harvestable. I added shiso to the ferment.
After a week or so they smelled good and the sun was out.
I sun dried both the plums and the shiso for several days.
That was too long in the sun for the shiso, it lost much of its aroma, though I crumbled it anyway to use as a condiment. Not ideal, but still nice. Salty, sour, and somewhat aromatic.
I put the shriveled apricots back in the umesu to age. I covered them with mesh and rocks so the liquid covered the apricots.
I guess the apricots absorbed the umesu and brought the level of the liquid down, because it got moldy anyway.
So that ruined both the umesu and the umeboshi. I'm quite frustrated.