Posting to separate Facebook accounts
1) Go to My Account > Settings > Social Accounts and connect a Facebook account.
2) Once it's connected, head over to Facebook.com and LOGOUT from that Facebook account
3) Go back into Stencil, and go to My Account > Settings > Social Accounts and click Add another Facebook Page
Once both accounts are added, you can share to any of the Pages they're associated with. You can do this with as many Facebook accounts as you'd like!