Implied Window Specifies Encounter

[Starlina]

Is it possible to make an implied window so that it will specify if the implied target is part of an encounter? For example, you could put an E somewhere in the window.

It is really difficult, as a warlock, to cast spells through the tank if I don't know if the mobs are part of an encounter or are separate. We use a completely different spell line. As it stands now, I am still using a /assist tankname key.

Thanks!