The GENERAL validity of 'senior citizen' bus passes throughout England has always been limited to the period between 0930 and 2300 on Mondays to Fridays. Some local authorities have VOLUNTARILY extended the scheme to allow travel outside of those hours (but usually only for those people who live in the local area).
With the current need to find financial savings, many of those authorities which previously extended the hours during which passes were valid are now restricting them to use only between the 'official' hours of 0930 to 2300. Here in Suffolk, passes (held by local residents) used to be valid at all times. As from 3rd April they're now only valid during the nationally agreed hours (i.e. after 0930).
So there are some areas where passes were never valid before 0930, some where they used to be valid but no longer are (or, will shortly cease to be so) and, just possibly, a few where they can still be used early in the day.
Chris