I'm using llbl 3.

If my initial query is in linq is there some way to tap into the provider to get the generated relation predicate bucket and add to it (mix linq with llbl queries). I ask this because I would like to append some common join on to my queries but I am finding that difficult to abstract in LINQ.

Could you give an example code of what you need to apply?

Like the query in this thread http://www.llblgen.com/TinyForum/Messages.aspx?ThreadID=19230

I want to join a query onto my ContextPermissions table to filter out records the user is not supposed to have access to.

It's been requested before, but at this point it's not possible to do so. One of the main painpoints is aliasing, as linq queries use aliasing for entities everywhere, so when you add your own predicates you have to use the same aliases: problem is, you don't know them when you write your code.