Help with AI JTAC - when are you cleared hot / told ABORT ABORT ABORT?

I've been practising CAS with a JTAC training mission I downloaded and then modified to practice Type 1 control, and different types of marker/designation. I can't seem to figure out why sometimes the JTAC will clear me hot, and other times I get told to ABORT ABORT ABORT after I call being in from north etc.

I thought it might be if I was not following the attack heading correctly (for example 180-270 means when you call in your nose should be pointing between 180 and 270 headings in other words you should fly from roughly the north-east towards the south-west). However this doesn't seem to be it.

Does the ordinance make a difference, so the JTAC will more easily clear hot a gun run but not a mk82 bomb?

Is distance a factor, so if the target is far enough away from the JTAC, they just clear you hot?

I have even (as a test), rolled in and pointed my nose right at the JTAC position rather than the target, and at a range of 1NM was cleared hot!

Also, I don't understand why the JTAC seems to choose attack headings that would make me fly near to their position. For example IP is to the south-east of the target, JTAC is north-west of the target and you get an attack heading that means you fly over the JTAC after dropping a bomb. I thought this should be avoided, as most ordinance is more likely to miss long than short.

Perhaps I am expecting too much of the AI JTAC?

I believe JTAC is broken.

I posted a thread recently and discovered JTAC will only laser on certain vehicles.

And have now resorted to using Mist to get a reliable JTAC