I'm sure I used to reopen a period and then keep A/P and A/R closed to create Journal Entries But now I cant... If I keep those two closed the period is no longer available to select in JE Am I taking crazy pills? Or just bad memory? 😆

Are you hitting an A/P or A/R account in your Journal Entries? Although if you're using an administrator role or a role with the "Override Period Restrictions" permission you should be able to post regardless of locked status (as long as the period isn't fully closed).