Branch Access

We have discovered that Tax Preparer staff are entering Branches on Saturdays (after Branch hours) and Sundays, alone.  This was reported during a recent Branch audit; however, management is pushing back on it.  Although it is a violation of our Security Policy, their response is to change the Policy.  We indicated that doing so would not mitiage the associated risk which we deem to be very high.  Do any of your credit unions allow access to a Branch during weekend, non- business hours?  If yes, do you have additional controls implemented?