Generally, if you are still employed or “in service” at the company that offers the 457 (b) plan, you cannot transfer funds from your plan. However, some plans may allow withdrawals during service once you have reached a certain age. Once you leave that job, you can move the funds to the account of your choice. You can also make a rollover by withdrawing the money from your 457 and contributing it to your IRA within 60 days.
It is not possible to make monthly transfers from your 457 plan to an IRA if it is a series of substantially equal periodic payments. If you are making monthly transfers from your 457 account to an IRA, you may want to consider creating a pipeline IRA to receive the money.