For now, based on the results of Jonathan's Google searches and Margarita's understanding of the expression, I have put it in the dictionary as 'to be in limbo'. Max commented that this may be a calque from English. This could well be true but I think Max would agree that, calque or not, if it is widely used with this meaning by enough Catalans then we need to document it.

If any of the Catalans on the list is familiar with 'estar als llimbs' meaning 'no estar gens informat tocant a una questió, ignorar notícies conegudes de tothom, etc.' and thinks an English equivalent for this meaning should be added to the dictionary, you only have to say and it will be done.

This would be "to be (completely) out of the picture" or "out of the loop". How would people say this in Catalan?

Estar a la lluna. (Estar a la lluna de València.)
ignorar / no estar gens informat tocant a una qüestió, ignorar notícies conegudes de tothom, etc.

Sinònims: venir de la lluna, dormir a la palla, estar in albis, quedar en dejú (d'alguna cosa), jeure a la palla, no saber de què va (alguna cosa), estar als llimbs.

Els que jo usaria són: estar a la lluna, no saber de què va (alguna cosa).