If you have rolled money into OSGP, you are eligible to take a distribution from that money at any time.
While you do not pay taxes when you roll over money from an eligible plan—which includes 401(k), 401(a), and 403(b)—or pre-tax IRA into your OSGP account, you will be responsible for taxes upon withdrawal of those funds from OSGP. Because these other plans and IRAs are subject to a 10% penalty upon early withdrawal, you may want to time your withdrawal accordingly.
Call OSGP at 503-378-3730 to request the appropriate form.