Thanks, Your responses have firmed up my thinking about the trees.
I have begun cutting all fruit from the trees.
They have been getting too tall to pick the higher fruit.
So, I will begin pruning to shorten the trees as soon as I've removed all the fruit.
To me, ripening is the fruit softening enough to be edible.
The Sharwil and the Ota are winter ripening.
The Lamb is a summer ripener.
It ripens in its second season.
The first season is too soon after blooming for normal size and ripening.
The tree normally will carry 2 generations of fruit.
The Sharwil had done nicely, delicious fruit up to 1-1/2# in size.
The Lamb's 1st fruit ripened in the second summer and was quite good.
The Ota while not prodigious, still had very good fruit.
All seemed to do well last season, the first after the eruption.
They all ripened early, though.
The Sharwil and Ota ripened in the summer, not waiting until winter with very few fruit.
Was caught by surprise, didn't get to try any of it.
The Lamb Hass ripened late in it's first summer with more fruit than the others.
They were small, but still tasted OK.
A few weeks ago, the Sharwil and Lamb began loosing a lot of leaves.
There was talk about a Lace Bug invasion on the island.
I found signs of sucking damage on the leaves.
So, I drenched the ground under the trees out past the dripline with a Neem Oil solution.
The Sharwill responded nicely and seemed to recover.
The Lamb has continued to decline.
The Ota still looked pretty good.
The Sharwil began dropping almost ripe fruit 2-3 weeks ago.
Fruit on the tree began to be ready to pick.
The young fruit have a shiny skin surface.
As they near ripening, the skin turns to more of a matt finish.
The Ota dropped its first fruit last night.
It was not watery, but fairly dry and somewhat tasteless, no oil either.
The Ota fruit begins to take on a yellowish color when it starts to ripen.
Some on the tree are showing signs of yellow areas developing.
It has begun to loose more leaves.
I'll try drenching its roots again soon.
I'm not waiting for the Lamb's fruit to begin turning purple/black.
I've begun to remove all the fruit.
It has lost almost all it's leaves, nothing left to grow fruit with, only a few growing ends left.
it will be severely pruned back soon.
EDIT:
The eruption evolved sulphur gasses, mostly sulpher dioxide.
This seems to have acidified our soil.
We have a hibiscus that was here when we bought.
It was doing very poorly.
After the eruption was over it came to life and began growing and blooming.
Apparently, it likes the acidic soil made by the gasses.
I've been adding dolomite to the ground under the avos recently to counteract this.