converted_gardener writes
I've pricked out most of seedlings and put into cells of moist JI2 and
put then in inheated propogators
They have all drooped

They often do that. You've given them a bit of a shock with
transplanting. You can't transplant seedlings without causing some
damage to roots.

Is this just the shock of moving or did I make the JI2 to moist , what
do you think , am I panicking ?

It wouldn't be too much water having an effect this quickly (I'm
assuming they drooped less than 24 hours after transplanting). Too much
water will rot the roots, so the plant can't then take up water and will
droop, but that takes a bit longer.

JI2 does seem to take longer to drain that multi purpose which is what
I've used before !!

How damp / moist should the soil be ?

Moist with no dry bits, but not dripping.

In one tray I filled them in from the top and in the other I sat it in
water and let it soak it up

I wouldn't have thought either had too much water.

I usually plant in moist compost, or water from top if the compost isn't
moist enough. Then if the surface dries out over the next day or so, I
add some more water.

See what they're like tomorrow.
--
Kay