Ringing secondary account buttons

Sorry I couldn’t think of a better topic description

FreePBX 2.11 asterisk 11.6.0

what is the best way to ring a different account line on a given extension other than the main account. I have grandstream phones with four account presences, where the main company number rings the first account for everyone, however I’d like to add two other trunks to ring select extensions on the secondary and thirtiary accounts (led buttons on the phone.)
I could have another extension setup for each phone and assign it to that button, but that will make extension management hard. Is there an easier or better way.

Thanks
Von