New DirecTv DVR symbols?

Does anyone know why new symbols are popping up on our DVR recorded list? There's a triangle with an exclamation point- that I found out designates a program as 'in danger' of being deleted but we still have 25% free. It only goes away when we have 50% available- why?? Also, there's a circle symbol with an asterisk sometimes. Also, if I'm trying to record a marathon, it will only record a select few...? Very confused and frustrated with these new changes. Any help will be appreciated.