May be just before 13:30 - don't be late!
Here is a full list of the timings posted on the RAF Marham Facebook page:
Tuesday, February 19
1.15pm - 1.30pm: Kendrew Barracks (RAF Cottesmore) - National Memorial Arboretum - DECA Stafford - RAF Cosford
1.30pm - 1.45pm: RAF Shawbury - DECA Sealand . . . etc